Focus on quality, predict possible problems. Think ten times, do once.
Use Your brain, keep Your emotions constrained.
Stay on subject. This project is about programming, focus on that.
Think before doing.
Share Your experience and knowledge.
Try expressing Yourself as clearly as possible. Not everyone is english speaker here.
Predict effects of Your action. You can be rude if You like but be ready to be beaten up. If You throw garbage be prepared to live in garbage.
Otherwise, be Yourself. We are thinking adults and do not need to be pampered.