Dreams can be slippery little suckers. You wake up knowing you have dreamed, but when you try to remember what it was, to put words to it, they can slip away and leave you with nothing more than a vague impression or sensation, like a mist at the back of your mind that clears gradually as the normal business of going about your day takes over.
That is why, if you can, you should try and take a couple of moments straight after waking before you get up and physically leave the dreaming space of your bed. Keep your eyes closed for a few moments, don’t speak – if your partner tries to wake you just murmur sleepily and roll over – these few precious moments can make all the difference in grasping at least a single image or word from your dream. Hang onto that, write it down. When you have more time later this single image will be like a key that lets you back into the dream. You may start to remember things that happened just before it or just after it – but in any case you should be able to build on what you had, instead of having nothing at all.