Anything Goes : Quick Survival Guide for Those Brand New to Film/TV by Laryssa Emeigh

I would add the target audience you are talking to at the beginning. You imply this is for new PAs but don't specifically say it until the middle. Next, rather than watching their fellow PAs, they should go to their supervisor and ask for the next thing to do as soon as they accomplish a task. Third they will get super bonus points if between their assigned duties, they keep track of the well being of cast and crew members. Ask people if they need water or a snack, then deliver it promptly. Look for cold actresses needing a jacket or blanket while waiting for their scene. Goose bumps do show up on camera.

I would like to add "Save the networking for later". I can't tell you how many times I've been on set trying to work, when someone decides it's a great time to whip out their business card. It has the opposite of the desired effect. The best way to impress people and have them remember you for future projects is to do your job, be attentive, and look for opportunities to go above and beyond.