When you first wake up, and don’t remember your dream, try not to just dismiss it and move on.
Sit in bed for just a second and try to remember, think of just dreams in general. Its funny how I can sometimes go from “Oh, didn’t remember the dream” to having a whole dream roll out before me.
If that doesn’t work, try to think of trigger words. These are random words that may have some involvement with the dream you had last night. These can be hit or miss sometimes, but they’ve helped me out a lot.
What to do: When you wake up, and don’t remember the dream, just start thinking of random words, (EX. Elephant, dog, vampire, computer, LD4all.) Words with no pattern of specific meaning. You could also think of places or situations, those work sometimes too. All the while trying to think of your dream.
The hope is, one of the words you think of will remind you of a fragment of the dream, then the fragment will remind you of the rest.
(EX, One of the words you thought of was elephant, and you suddenly remember riding an elephant in your dream, and then you remember your dream was about you going to the circus or something)
It might not always, work, but it’s worked for me, and it’s worth a try.