Is there a good way to manipulate where he goes after you smack the eye for the first time? I can never get a good fight and have tried 20-30 times for practice and getting frustrated by it's movements for the first bomb/slash attack

Really you just want to be stood in the middle of the arena so it won't go there. Beyond that, I'm not sure.

He always goes diagonal so just stay in a diagonal from him and he'll attack in that direction, you just need to be quick enough on the bomb + spin. It's pretty easy.

OK, cause after the first time I use T-Rod to slash the eyes and he reveals the disks, I always end up directly left of him, and can never get the bomb + spin in time and he wrecks me so I can't really get some good practice in on him. After the first disk is broken, I can always get diagonal from him, but never after slashing the eyes.

Just don't stay too long in top of him, it's easy to tell when you've hit him enough times so you can hop down and go to a corner of the arena for the manip.

OK, so the easiest way to go to a corner of the arena and will that guarantee to get diagonal from him?