I think when u sleep u already are meditating, because your body is already relaxed while laying down. Even while your dreaming your mind is focused on one thing. It may seem like it’s hard but technically it’s already given to ya. All you gotta do is relax without any stress or anxiety or even worry. As long as you can breathe without any negative thought or feeling you can get it down. It’s a wonderful feeling if ya ask me. Give it a try. Cuz it helps me quite a lot.
I usually have a lot going through my head, but sometimes I just try to listen to the sounds around me and see which ones that I can’t hear as clearly will stand out to me. Since your focusing on the quietest sound it helps you stay focused and calm while not falling asleep trying to find it!
I would suggest that you do it earlier in the night. It seems the time you are using to meditate is the same time that your body needs to rest.