The ACU publishes a supplementary regulations booklet for competitors with all that sort of thing in.
The main one is that, at the TT, you must stop in the stop box, at the top of the pits and put your feet on the ground, before driving on into your pit. This is, of course, a safety measure.
Your pit is allocated a short time before the race, and will be based on a pattern which hopes to ensure that riders likely to come in for stops at the sam time are not in adjacent pits. Doesn't always work, but here you are.
There are regs about how much fuel / what kind etc, you can put in your filler, and when you have to remove any surplus.
Lots of fire regs, such as fire resistant overalls...
What else do you want to know?