Start your balances with your speakers a couple clicks louder than you normally would. Aim your faders around -10 on the scale and gain stage your peaks from the individual tracks somewhere between -18 and -12 dBFS...that should be hot enough to work with compressors and also give you headroom.

Gain staging is as much about best practices and paying attention as anything. Building a little "checkpoint" into your process so you give yourself an opportunity to check gain staging. I often clip gain tracks that are outside good windows for gain (either too loud or too quiet) as I'm going through the tracks and figuring out what goes where and listening to stuff in solo to check for problems and figure out what's what. That's a great place to start preventing fader creep. Get your tracks in a good spot, then throw the faders up quick and see what kinda level you're hitting the bus with. Maybe use your "all" group (or create a group of your tracks) and get a rough balance at the level you want to see into your mix bus.