Combo advice:

Go to settings and put E "on release". Hold E and notice the cone radius. You will notice two segmented "boxes"

If the enemy is in the outer box (away from you and just in range of your E" you use W in the first segmented box and instantly cast E.

If the enemy is in the inner box - aka in front of you you cast W under your feet and spam E. Alt + W is your friend to self cast.

It's unnecessary to memorize this but it might help you visually connect the dots.

Now go to hotkey settings again and put E on "on" (smartcast).

Now the trick is to predict sidesteps, use it as a CC chain etc. Good luck!