Guide is a huge pile of text, Mejai is a ******ed first item, Kat has 2814721984791874 counters in lane which you hardly mention how to deal with and you're clearly used to play against people who blow all their **** in one rotation so you can just go in and ult with your amazing 800 AP.

Your build is questionable because it doesn't fit any possible scenario. You need to conclude a standard build path and just mention Mejai's Soulstealer in a sidenote. There has to be a more defensive start options, alternative boots and overall your ability sequence should look like this: Fist ability maxed at level 9, second at 13, third at 18.
Replace Enchanted Armor with Block in the Masteries and everything is fixed!