evoker is very easy to spec, easy to gear (all you need are good weapons) and scale infinitely with knowledge and skill
different people will tell you a lot of different things and it's likely that you'll be making alot of mistakes with skills and pissing away alot of palladium on useless gear
What I will say; 10/10 Flameshards, 10/10 Demonspine, 10/10 Hellfire, 10/10 Arcane Shield, 7/7 Dual Focus, 1 in Blink, rest in Spectral Curse
if you actually care for in-depth detail on anything and everything about the evoker feel free to send a PM