Go to bed at the same hour every night, and get up at always the same time. This will reinforce your sleep schedule and eventually you'll wake up by your own. By doing that, it's most certain that you'll remember your last dream. Sometimes other factors (like stress, or food) can affect your dream recall, but at least one dream per night should come You can always check the Dream Recall Compendium and find some other tips there.

Moving this to Dream Signs and Recall.