I am going for a gamer mode single player speedrun, but I always mess up on the fight? if I could get some tips on how to dodge his attacks that would be nice

Stay close to him while circling clockwise for the most part. When he does his flurry of swipes, he'll put both hands up if I recall, you need to sprint to get behind him and out of his range. When he goes to throw his swords, he puts one knee up, just sprint and try to stay as close as possible while circling, if you're close enough neither thrown sword will hit you, although the knee he puts up for the animation makes it a little difficult. Finally, when he does his slam attack, where he puts both swords together, start sprinting directly away from him a little after the animation starts and then jump once you hear the sound effect of it being fully charged, you should hear it just before he actually slams his swords down, and you'll jump right over the projectile. This usually works for me. I'll make a video about it in a day or two if you find the explanation hard to understand.

this guy explained it very well but basically never stop moving.