[{quoted}](name=Gives No Lux,realm=NA,application-id=3ErqAdtq,discussion-id=c7aA7iQ3,comment-id=000100000000,timestamp=2017-12-11T08:43:29.054+0000)
It's mostly about practice and getting a good feel for her mana pool. For example to take advantage of Doran's Ring you don't want to burn an entire wave down with your ult. Throw it up long enough to get them low and maybe toss an E at the cannon then turn it off and last hit to finish the minions off. That way you save mana form ult and you're maximizing the benefit from Doran's.
If mana is holding you back over survivability then I would say get tear first, then catalyst then finish RoA. If you're judicious with managing how much you use your ult then tear and catalyst should be enough to ride you out through mid game.
I still think her mana costs can be toned down a bit.
Q: 80-120
W: 70
E: 50-90
R: 40 per second.
Her starting mana is like 396.
Buy dorans, ok cool.
starting ad is like 60
one q plus e at level 1=130 of that 396.
Now realistically you're forced to play passive.
3 q+e=390 of that 396. Now you're useless because her basic attacks are weak and if you're playing against a poke champ like
you're forced to back losing more cs and letting him take the lead in cs and kills maybe.