Look down, left and right from where you will be working. if you see anything with paint on it, cover it with a fender cover or a couple of heavy towels. Tape them in place to keep things from moving.
Don't put tools on the seat or balance parts on the gas tank
Look where the wrench is going to go when you discover you are not fully engaged on that bolt (nut). Is it painted or coated (see first note)
Make sure you have all the necessary fastners before you start taking things apart. Chase all threads before you start
Torque values are provided for a reason.
When you spill it, clean it up before you fall in it.