This is what I can think of at this hour.

You will be on the set in time.
You will be well prepared.
You know what´s expecting from you.
You will have a current AIM test. And only accepting working with talents that have current AIM test.
You will smile and fuck the male/female talent even if you hate him/her. It´s your work and the producer is paying you to be a pro.
If your agency forget to give you all the information you need for the scene, then go to an other agency.

And never forget, there will always be new talents ready to take your work if you can´t handle the bizz.