How to prepare for an OTB tournament?

I'm attending one in a couple weeks. What should I do in preparation for it?

If you know the time control try playing as many games as you can with human or non-human opponents at that speed.

Know as much of the rules as you can.

Stay/get healthy.

Best wishes.

Revise your openings, Don't touch bullet or fast blitz for a while (stick to rapid/standard games), do tactics (at your level, it is integral), revise your basic endgames, play against stronger players here, and also if the pairings of your tournament is released, check your opponent's repertoire and prepare against it accordingly.

Frankly, there's not a lot you can do in a couple of weeks that will make a huge difference, so the best thing may be to not worry too much about it, relax and enjoy it.

If the tournament is a slow time control one, and you don't have much experience of that, it's probably a good idea to get some slower games in beforehand.

If you always struggle with some common opening, it might be time to look up where you're going wrong. Even so, that opening might not come up at all in the six or so games that are played in the typical weekend tournament.