This ap shaco support build isnt made for beginners that are just picking up ap shaco support, the sheer amount of info and experience required to play it to its highest limits with the playstyle below will most likely overwhelm you and will require a lot of playtime with it to master.
I would reccomend Rolocyns "How to make Adcs disappear" guide.
Link: https://www.mobafire.com/league-of-legends/build/how-to-make-adcs-disappear-647013
As their build is better for newer shaco support players as double burn will give you a higher damage output if you cant do all the setup and micro in the playstyle section below that is required to bring out this builds full potential.

As requested, this is an explaination of my ap shaco support playstyle, i wont comment on the other builds like ad, debuff ect because i dont play them enough and i dont think theyre as strong.

For starters, what is the true purpose of ap shaco support? and how can i make ap shaco support stronger? its a question i had asked myself alot over my nearly 3mil mastery of playtime, and in my opinion the purpose and true essence of ap shaco support is: CONTROL!

No other champ or support has as much control as a haste and ap maxing shaco support does, with a max haste and ap build your damage, vision control and area control skyrockets based on how many boxes placed at once in a general area through stored overall damage potential, i get to overdose on vision and area control with the up to 21 boxes, 3 wards and blue trinkets.

I believe with the sheer amount of control i have that its better to overdose on vision control with a blue trinket past level 9 rather then clear wards with oracle lens, as since i like to prep 1,30 - 2 mins beforehand, i get to know for certain that once the obj spawns there will be no vision as all wards will have despawned since i was controlling that area while prepping it and no new ones could be placed, wards only last 1:30-2mins.

Leashing:

The first part of my playstyle is relatively simple to do, on spawn, place a box covering the river extrance next to midlane on the botside jungle, then at 50 seconds, place your first box on the buff, then at 1:05 place your next box and immediantly recall to refresh your mana bar, you dont need to stay in base until its full, immediantly walk to lane and you should have around 93% mana, which with regen is enough to last until you have the 300g.

Laning:

The second part of my playstyle is, bush and vision control, once you arrive in lane walk towards the middle bush, be careful if they have cheese potential, if you dont see them arrive in lane as they should get there slightly faster then you from a leash, then be cautious of the first bush, dont be afraid to use your sweepers when walking towards it so that you will see their red outline in the first or middle bush, have your box at the ready to block them and predict the hook ect by placing it between your immediantly as soon as you see their outline, if they have a hook champ, dont go for this, just wait with your adc and ping them to be cautious, if the enemy doesnt show, then you know for certain that they are in that bush, get ready to boxblock for them when they step up, if they arnt there, then keep walking towards the middle bush, if the enemy support contests you going into it then simply box it so they dont have control of it, if you do get control of it by walking into it, then box the bush closest to their tower. if its safe, try to do some vision mindgames, walk into the bush closest to their tower to see if you can bait them into warding it, if not you now have control over all 3 bushes, if they do ward it, then simply go back to controlling the middle bush knowing that theyve wasted a ward.
By gaining bush and vision control like this, it allows you to sit and wait for the enemy to make a mistake, and it allows you to invis engage from out of vision. if you lose control, then move to the walls of river entrance to use as engage points, learn the vision radius of minions to know when you are seen/in fog of war, sometimes i will fake Q on the spot to check if a bush it warded by watching the enemies reaction to it, or barely step out of a bush and Q back into it to make the enemy think that im engaging, when in reality im giving my adc breathing room to farm the cannon.

The third part of my early playstyle is, Technique, to be effective on shaco support, you need to learn the micro of your champ, get your friend to go into practice tool with you and learn how to boxblock and Q buffer everything, the threats page above tells you everything you need to learn how to boxblock and Q buffer, by knowing how to do this effectively allows you to become more of a threat and to give your adc breathing room, a hook thrown at you and blocked/buffered/dodged instead of your adc gives them breathing room to do their thing or go for a trade.

The fourth part of my playstyle is, laning, i see shaco support as like an egg waiting to grow, the more gold you feed it the stronger it becomes lategame, this version of ap shaco support is a lategame hypercarry, adcs dont like shaco support because they see it as useless in the early game, which i kind of agree with, so i tried to make ap shacos early game stronger without sacraficing its lategame potential, which is where i came up with the tp tech, as it allows me to double my early damage and lane pressure by allowing me to use all my mana as effectively as possible, it allows you to go for plays like the E Q quicktrade without having to worry about the mana cost, where you throw E at the enemy and Q forward to crit them at the exact same time, with practice it is possible for both to land at once from your max E range, the closer you can get to landing them both at the same time the less reaction time your enemy will have to punish you for it, and it chunks like hell if you can get both the E and the Q crit to backstab early game. most early games that end at 15, i will actually have more damage then my adc by using these quicktrades and having the freedom to use more mana. (just note, the E Q quicktrade is extremely risky, only do it if you know the enemy cant punish you for it or are bad at reacting to it, as you are using your only escape!)

Post ~14 Mins:

The fifth main part of my playstyle, objective prep, overdosing on map control and forcing fights where i know i have the advantage. the river vision bridge, or bridging for short, most higher skilled supports will do some form of bridging, some with deep wards in the jungle, others will vision bridge the river bushes instead, shaco has the power to do both, usually past 14 minutes i will start getting my advanced bridging setup online (mainly because thats the timer of the 3rd dragon spawn accounting for the 1:30 prep time and time between dragon kills), completely locking off one side of the map from roams and ganks starting from the river, then later in the game i will slowly start expanding into the enemy jungle as i gain more control power, through being able to control more boxes, it only takes 3 boxes to bridge the river chokepoints, if i lose control of the enemies jungle from a decent support then i change my plan and start condesing the boxes in the area i do control in the river to prepare for the objective teamfight, but its rare to lose control unless youre late to your prep timers.

The sixth part, jungle control, Bridging is also insanely impactful for seiging aswell, imagine your team is doing a 1 person split top and 2 mid on the teir 2 or 3 towers, your job is to control the jungle between them with boxes and vision, this will allow your team to be safe from the side of the jungle you are in, and will also allow your jungler to farm that part of the enemies jungle freely, it allows both you and the jungler to respond to threats to the 1 person split and the 2 person seige mid, try to have some fallback options behind the seige mid, i will always be hugging midlane to setup more fallback options if they have high pick potential like a hook support or high burst champs, try to have one of your wards on the opposite side of your jungle bridge so that you will be able to see threats coming towards midlane to allow you to respond to it faster.

The seventh part, is an alternate form of the previous one, as a lot of lower elo teams wont know how to effectively do a 1-2-2 split as top/bot through the jungle to mid, so this form instead focuses on a slow seige, where you slowly creep up a lane while setting up boxes/wards along both sides of the close enemy jungle with boxes behind you as fallback, this version allows you to see any flanks if done right and have relative safety from the boxes behind to fall back to if they fight it.

The eighth part, which i never see ap shaco supports do, and is kinda unique to my build as its the strongest while haste and ap maxing, it is: Splitpushing. if the enemy team has a stronger teamfight potential then yours, or if your team is more engage outside of your boxes rather then kite and fight them in the boxes, then splitpushing is a viable and extremely strong option, by going into a lane and slowly setting up your up to 21 boxes (do not push this lane, thats not the point even though its a split 'push', you need time to prepare), the more boxes you setup behind you in this split, the more of a threat you become to the enemy team, you will have the power to 1v1 or 1v3 depending on what they send, regardless, this is ALWAYS good for your team, as they cannot send the support to deal with you, you will just outpush and kill them, if they send 1 and the support, then you will still have more power and will slowly wittle them down, if they send 2 carries, then that is good for your team as your team with have 4 carries verse 2 of their carrys and a support, which will usually result in a teamfight win on that part of the map, your job is to make yourself as much of a threat as possible and waste the enemies time, if they hard push you back, then backup and let them chase you into the boxes to deal insane damage and usually trade 1 for 1 if they do catch you, if they dont, then you can stay and reset your fallback, you want them to either stay with you or die to you, the longer you can keep up with split threat the better. if they dont respond to your split, then you get your full setup and break their towers.

The ninth part, if theres no applicable seige and no splitpush opportunity, then tell your team that youre prepping baron and look to prep the enemy topside jungle to prepare to force a baron play, if you manage to setup your boxes for at least 1:30, then tell your team that you can force a baron fight now, even if your team hasnt gotten a pick, you have the advantage, have your team start the baron, do not be on baron yourself, you are the distraction, drop clone as the enemy comes through or chain fear and run, do not full engage as if you die then its really bad, your team can either finish the baron if applicable or turn and fight the enemy team that youve just chunked out with your setup of boxes as they force their way through to it.
Immediantly after we get a baron i back and pretty much always look to teleport to do my sidelane split strategy if i have tp up, as it becomes a lot more of a threat and the enemy team is forced to respond to it with 1-2 champs. if i dont have tp then i default to one of the other strats while my team seiges or splits with baron buff.
If something happens while you are prepping this baron, then immediantly stop and respond to it, as its pointless setting it up if your team has a disadvantage.

I will ALWAYS be doing one of these 5 post 14 min setups, as it allows you to push the limits of shacos damage by setting up your boxes in a single area through stored damage potential, always prio doing your 1:30-2 min prep timers before objectives.

This all probably seems a bit advanced coming from a plat, i just play for fun, never really got into ranked, only played 18 games of it this season, only play it when my adc wants to duo queue, the 70.8% wr is from the 195 norms games this season, vs a lot of dia/masters in my games though when i queue alone, i just prefer to have fun instead.

Ill chuck this down here aswell incase anyone wanted to see some of the things you can pull off with shaco, the vid is a bit old, made it 10 months ago, but still showcases some of my best plays.
Link: https://www.reddit.com/r/shacomains/comments/1fzyxml/5_mins_of_ap_shaco_support_chaos_incarnate
Btw, if youre wondering how to spawn clone closer to the tower like the velkoz clip, the trick is to turn after Qing at the exact moment the clone teleports to you, as the clone will always spawn behind you when leashing back to you, and since its closer to the tower on the tick that the tower will aggro then it will always tank the tower even while youre Qing into its range. a gift of advanced tech for the experienced shaco sups to pull off in their games.