1. Have someone to watch your back.
Last I checked, you can't grow eyes in the back of your head and you eventually need to sleep or hit the head. Or patch you up when injured. Situational awareness is big, but you've got to have someone else who you can count on to watch your six and stick with you through hell and back. Those people are often few and far between, and those relationships should be valued and cared for.
2. Be prepared to walk away.
Things go bad. Good situations can turn to crap in a heartbeat. Sometimes you can stand up and fight, but often times getting out of dodge is your best bet. You don't want to get stuck between the hammer and the anvil. You've got to be able to drop it all, grab and go at basically a moments notice. Have a plan and a way out of harm's way.
3. Focus on what matters first.
You've got a finite amount of time/energy, so you need to work on the important stuff first. The stuff that matters the most should get your most attention and should get that attention the soonest. The other stuff can and should wait. This is a huge thing--it's all too easy to become distracted--but getting a handle on this is really important. Always good to take a moment to step back and think about the direction you're moving in.
4. Have a Plan B.
Gear breaks and the best plans fail--Murphy's Law and all that. Backups keep you alive when things go south, whether it's redundant equipment, an alternate route or contingency plans B through Z. In a time-is-life situation, you're not going to have the precious time to sit there and troubleshoot or rethink what you're doing. You've got to be able to transition quickly and aggressively to a backup plan.
5. Capabilities trump gear.
There's something to be said for having the right equipment, but a survivor's actual capabilities--skills and physical abilities--are what matters most. When things go bad--when there's stress, when there's pressure--then your capabilities are put to their test. If you're going to succeed, things will need to be near autopilot--don't count on having the time to think, fumble through and figure things out. You've got to be able to flip the switch and act, and that takes practice. Lots of it.
What are you thoughts? Agree, disagree? What other "rules" do you prep by?