I do 5,4,3,2,1 - I think about:
5 things I could see (as it’s dark I can’t actually see them so I think of things I have seen, usually on a theme like 5 beaches, 5 lighthouses, 5 trees),
4 things I feel (my head on the pillow, my leg against the mattress and duvet…),
3 things I hear (a car in the steet, my husband breathing),
2 things I can small and one I can taste.
The last 2 are a bit more difficult but I’m usually asleep by then so it doesn’t matter.
More recently I’ve been running through a dance routine I’m learning - that works too.