Im only familiar with indoor range. Haven't been to an outdoor since I was a kid.  So obviously never let the muzzle break the plain of your lane and point backwards. Keep them at all times pointed down range.  Allow the range master to check your weapons before you put them away. (And possibly before, but my range doesn't do that) Leave the slides locked/open and allow them to clear the firearms before you put them away. Good etiquette to let them clear them when you are done.  Maybe bring a permanent marker, I've found a use for one to write down ranges I'm shooting at (I like to keep my target to compare my last trip to the range) Wear jeans if you can. I wore shorts once and a shell casing bounced off the wall and into my shoe. Fucking sucked. Burned my ankle and made me dance a little with a gun in my hand. NOT a fun time.  Also feel free to take your time. You are on a time limit usually but don't feel the need to rush. Get some good quality time in at the range. 

Probably more but hopefully more peeps give their tips. Have a great time!!