At level 1, you want to hit most of, or all of the minion wave with your E and your lane counterpart then auto attack your enemy laner and as many of the minons as possible (Casters then Melee).

At level 2, to poke your lane counterpart you want to hit them with your Q, autoattack. While you are sending out that first autoattack you also cast your E. The moment that your first autoattack hits you detonate your E and send out another autoattack. Tons of damage.

At level 6 and beyond, to delete your lane counterpart you do the combo shown above but add your ult in at the end, if they don't die you can probably follow up with an autoattack or a flash autoattack.