Congratulations on the upcoming interview!

Not sure your field or exp level at all to give specific guidance, but my main thing is to try to give yourself grace after you get through it. You won't be able to help second-guessing everything, but things work out however they do. If you aren't selected, it's great to build experience going through the process. I'd recommend reaching out to the point of contacts post-interview for any feedback they can provide you with.

Edit: since you are specifically asking about pre-interview... My habits tend to be researching online about common questions for ppl in my field + just practicing my responses aloud. Going through the motions a few times beforehand makes me feel more prepared, whether those responses get used or not.