Write them down!
Immediately, no potty breaks. Get a felt tip marker (you tend to write flat on your back) and 2 notebooks. One for notes after every dream. The second for a neat transcription in the morning, along with anything else you remembered, and impressions, etc. It really makes a difference. I've come to realise I get 'lessons' most nights, now if I only knew when the final was!
I cant always wake up to write dreams down, so when I'm lucid I dream about an empty room. I find an object that summarizes the dream and put it in that room. Every time I remember while I'm sleeping, I keep putting things in the room, and look at everything else in it so they dont disappear. When I wake up, I remember about half of the things I put in there.
Other times I think I'm awake and write down the dream, but I only dreamed I wrote it. Not a problem. The next time I really wake up, I expect that stuff to be on the paper, and when its not, I remember and write it.
Rastus has a good idea. Writing them down just after you wake up will help you retain that knowledge. The first LD is always the most difficult to attain. It may be a slow process, but gradually you will have more and more and they will last longer. After about a year I am now able to have sometimes 10 LD's just in the period of a nap. They are hard to practice because often times they are random. But as random ones occur you will be able to recognize them much better and eventually induce them willingly.
Since I'm only new a practicing for LD, I can't remember very well dreams. But I just remember that my first dream was LD. I only remember the part where I think about looking at my hands, I look at them and they melt. Just after this short LD I was semi consciencious and I remember that I tried to remember the LD at this time.
And for the rest of the night, I had several dreams and between each dreams I was semi-consciencious (which is not usual) and tried to remember each dreams. But this morning I wasn't able to remember any dreams, just what I told you.
I guess I just need to practice remembering my dreams. And to do so, I think I'll use a microphone which is going to record non-stop all the night. Writing down the dreams needs too much concentration so I need to be fully consciencious, but with a microphone I'll only need to talk. Talking is more natural than writing, isn't ?
It's so exciting, having a LD so early in my learning, it gives me hope a better experience in a near future. [:D]