If you play that type of build, you will focus on your autohits and your q, first apply your w, than start doing q - autohit, q - autohit.. that will give you a bonus dmg on every autohit, but be carefull, sylvanas is squishy as f***

this guide will be really hard to execute, only do this with a good, premade team.
use ur ult as often as possible and do some merc camps, than just simply push, you will get into it ^^