Cho'gath Guide

Tips for Playing Against Cho'gath

-Be careful of his E (3 auto attack spikes), ESPECIALLY if he has hail of blades. It does percent max health damage.
-Movement speed can help a lot with dodging his Q.
-His Q and W both interrupt your W, so be extra careful about getting ganked.
-Be careful when you're low, and if you're ahead enough and the wave state calls for it you can probably fight him after first back.
-As with other health-scaling champions, keeping the wave back near tower can be a good idea so you can spit them into tower. Tower sometimes gets you the damage you need.

Swiftness Boots

Swifties are very good for dodging his Q, and not to mention his E and the latter part of his Q slows, so it helps with that too. Dodging abilities means surviving AND fighting him easier.
Hollow Radiance

Hollow is probably good. Haven't really tested it but, waveclear and magic resist... I usually just go Heartsteel though, which is probably your best option if you're winning, or if there's a lot of squishy enemy champs.
Redemption

Super cheap item, and does 10% max HP damage, plus you can guarantee to hit it with your ult, which also does % max HP damage. I think this is super under-rated, but I'm still testing it thoroughly.