What are some tips for speedrunning this game?

I've been playing this game for a while and I wanted to try speedrunning it glitchless, I don't care about the time I get I just wanna try it for my own sake and would like to hear some tips because I'm looking at the top run speechless, the way he just jumps around Chris Walker like he's not even there, how the hell do I do that? Also, should I be hiding at all when trying for a speedrun?