I have a ridgerest I take everywhere. The trick for me is find some softer soil or gravel, be really tired, and mentally relaxed.
If you are still thinking about work, how early you need to get up, your guylines, kids, mosquitoes or bears, it can keep you from descending to REM. If you are really type A, some relaxation techniques may help.
An alarm can really help you sleep, ironic huh?
Edit: I sleep well with an alarm if by myself, but with friends, I worry that it will annoy them. In spring around here, there are reliable bird sounds to wake to.