Everyone has their own process. Some guys get really worked up and emotional, other guys have superstitions and if they have so much as a sweaty towl out-of-place they feel like they'll lose, and still other get real stone-cold and don't like to talk to anyone or even so much as move before warming up.
I think I personally have always been the latter. The last thing I want before a fight is human-contact. Unless it's someone I trust enough that they won't attempt to infiltrate my focus. I like to do the traiditonal Bushido meditation regarding Death, picturing every worst possible outcome of the fight. This is very cathartic, but it allows me to go in with a clear conscience no matter what happens. I block out everything, including my opponents. It's not a wether I will or will not kick his ass. It's that I've ALREADY kicked his ass in my head. The work has been done, that's what training is for. Everything should work like a machine, flip the switch and it happens, no hesitation, no second-guessing. If he counters the initial plan, that I am not really thinking in-the-first place allows for the paradox of being a thinking fighter. Adaptability. Because the motions are like mechanisms and not really based on effort or a thought-process, you're free to invent and change directions.
The opponent is nothing more than an obstacle, a job to be done to me. Like as if I were a wrecking ball and he is a wall destined to crumble.