I'll skip all the boring part of this guide that most people won't read. So who am I?
I am a Shaco main with a lot of knowledge about the champion. I have several accounts sitting comfortably at various ranks but my main (Lil trash) as of now is Gold 2-3. I've managed to hit Platinum in the pat seasons but I've never managed to stay there till the end of any seasons my highest peak after dropping down to gold 1 is p3 where I was playing shaco there every time.

PROS He can escape SO easily
He deals a lot of damage
Has strong early ganks if the player know how to gank
Really fun to play
Can counter jungle so hard
Can melt towers and objectives with his R
Can tilt enemy team

CONS If set behind its really hard to comeback
Quite squishy
Hard to learn/master

As a shaco you need to be the most annoying person in the world. I always try and steal buffs early on.
So if the enemy jungler has no mana start with your red and go and steal the enemy blue Play Video

Shaco has strong ganks just make sure you don't always gank the same way because you end up being predictable.
Red side ganks
http://prntscr.com/o9lo6i
http://prntscr.com/o9lpmt
http://prntscr.com/o9lqio
http://prntscr.com/o9lrff
That's it from the red side. Lane ganks are also a good option
Blue side ganks
http://prntscr.com/o9lso7
http://prntscr.com/o9lt3a
http://prntscr.com/o9ltyv
http://prntscr.com/o9luiw
->Note that you can gank from the enemy jungle since as shaco you spend a lot of time there but these ganks are a bit "riskier" since you might get spotted by the enemy jungler or you might be seen by minions(check mid lane gank on red side). Other than that depending on the situation you can choose from where you want to gank. In some ganks(early ganks) you will have to first walk some of the distance and then use your Q since you will be revealed way before you have reached the enemy players

I'll make the guide even MORE in-depth if i see people using//viewing my guide a lot. Thats all for now!!
Have fun playing and make sure you tilt the enemy :)