In my experience, when you don’t want an alarm clock or lights to wake you up… AUTOSUGGESTION can be a very valuble tool. When i first started my quest for good dream recall i would say to myself while falling asleep “I will remember my dreams tonight.” usually i would wake up after a dream ended, but it worked.
also keep in mind that your prospective memory can really help you when using this autosuggestion method. if you plan on trying this to improve your dream recall, then it would behove you to practice some simple prospective memory exercises.
A post about prospective memory has been split to it’s own topic in General Lucidness, “Training prospective memory?” 