Just harrass with your q only. Dont use it on minions, only use other spells when you can get a kill. Conserver your mana and you won't need a manamune for AD ez. For hybrid ez however, I get a AA late game because hybrid spams all skills on cd, eating through mana like crazy.
I play hybrid ez pretty exclusively since the patch now. My build for him starts out like an AD build that hybridizes, then goes AP.
(exhaust/flash armpen quints and marks, cdr seals, no glyphs I'm poor 21/0/9)
Sell guinsoo for second hextech.
I start mana sapphire with 2 health pots and rush that sheen asap! (I'll blue pill at 860 gold). If you are really having trouble with your mana; when building the rageblade and gunblade, start with 2 pickaxes and focus on just mystic shoting. I love this build so much, I have tonnes of armor pen from my runes so I blow up squishes super fast in ganks/team fights (shifting over tanks/walls/w/e) and when I get jumped by a tank or a bruiser, I can ususally kite them and heal their damage.
End game, this build has 240 ad and 747 ap. With lichbane procs on mystic shot, you'll hit for 1.3k, and ult for 1.4k. W and E hit for like 600+, all the while you get 40% life steal on your Auto attacks and 50% spell vamp on your spells.
P.S. I love cdr on ez. Gotta make sure my shift comes up as fast as possible. Also, thinking of dropping flash for rally. I know I know, rally is so troll, but my sheen seems to be applying my total ad to mystic shot, not just my base ad. I have yet to try it, but I'm thinking the extra 10 ad and 20 ap right off the start will be quite impressive.
EDIT: I take back what I said about rally, I thought it'd have a low cd for how garbage it is...... 270 seconds? lolyeahright.