If you can use your Q (Sifhoinig Strike), kill a minion with it! Sifhoinig Strike is improves every time you kill something with it.

Do not forget this HUGE advantage of Sifhoinig Strike: it is hurts turrets! on the ather hand, your E (Spirit Fire), isn't reduces their armor.

Your W (Wither) work very good with abilities who pulls the enemy, like Blitzcrank's Rocket Grab or Vayne's Condemn. Try to work with those champions, and you will be legendary!