Before you get 100 stacks on your passive you need to think what ability should i use with the 100 stacks when on the passive? so here is how you should use each one of them:
Q: Your Q with the 100 stacks on passive is a deadly thing! you should use it when you fight someone, but dont use it as ingage tool, use it only when you fight or chase enemies that slower than you only if they are in the range of your ability.
W: Your W is not a ingage tool but its good for chasing and running, when you chase someone with the 100 stacks on you, it can be very good to use your W because your damage is on your basic attacks at this time and you can chase the enemie with the W at the same time, when you runn away jusr hit your W button and you are done! Gj! i dont think someone is dumb enouth to not think about it. wow i dont think someone even have time to read until this point.
E: Your E can be very deadly in 1vs1 fight after you get a bit items and it can be a toll for running and chasing, when chasing... just hit E twice on the enemie to get the max slow and when you runn.. just dont be dumb and do the same thing
R: Just kiding you ult dont scale with your passive

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Play super agresive, and remember most of the times you are the stronger top laner from the 2 of you just spam you Q and the enemie will never get close to the minions because if he will do you will jump at him! and do a lot of damage!!

Remember, If you have more than 50 stacks on your passive you get bonuses on your abilitys, you get 20 stacks for every ability you use, not including your ultimate, here are the bonuses:
Q: 50% more damage
W: Bigger shield and more speed
E: bigger slow and 50% more damage for each rocket
R: Nothing, Just Nothing special
because your abilitys have a low cooldown and you dont have mana, you can get higher than 50 stacks easly, you should try and have 50+ stack every time even if there is no enemie close to you

If you buy zhonyas you can activate is while your Q is up and its will still do the damage, just a small and nice tip :)

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Credit To Frost Prime