Ride within your limits and comfort zone. Don't push it. It's safe, but can be dangerous if you're being stupid--e.g., going too fast, not paying attention, etc.
My personal rules of thumb (assume each is prefaced with "when safe to do so"):
- Keep an eye in the rear view mirror. You will be going faster than some riders, slower than others. Let the faster guys go past.
- When someone moves aside to let you past, give them a little wave. Reinforce good behavior.
- Know how wide your bike is. My FJR's mirrors are slightly wider than the saddlebags. If the mirrors clear, the bags will. I'm still adjusting to lane sharing with my GSA.
- There will be people who won't let you pass. Just back off and wait for a safe opportunity. They're being asshats, but if they hit you, you lose.
- Be aware that car drivers often don't see you coming and when you go past them they will be startled. Even in LA.
There's other things, I'm sure, but that'll get you started.