There is a sticky "Remembering Dreams " topic in this section.
https://community.ld4all.com/t/the-big-remembering-dreams-topic-part-ii/9233
I find you need to lie still for a while when you first wake up and try to capture any fragments of dream and then slowly capture more of the dream. If you wake in the night, it’s important that you write down the main parts of any dreams that you remember otherwise you will probably forget them by the morning.
Good Luck. 