Learn to value your dreams. Treat them as friends and like friends they will visit you more often.
In a calm state of mind before falling asleep, think "I am willing to receive your messages."
Have pen and paper, or tape recorder handy at bedside. If you don't want to write down an entire dream when you awaken at night, at least record a few key images. In the morning you may be able to recall the rest of the dream from these notes.
The longer you sleep the better your chances of recalling a dream. This is because each dream cycle occurs about every one and a half hours, and earlier in the night during deeper sleep you may only dream for two minutes whereas during the lighter stage of sleep, right before morning, you may dream for thirty minutes or more.
Train yourself to wake up naturally, or get a clock that awakens you gradually rather than suddenly. There are sound "alarm" clocks with slowly increasing volume and light "alarm" clocks that simulate the rising sun.
When you awaken, remain still and keep your eyes closed. Focus on the area at the center of your forehead and ask yourself, "what was I dreaming?" Allow any dream experience to come forward.
"To me dreams are part of nature which harbors no intention to deceive but express something as best it can."