Little changes that helped your baby sleep better?

Is there any small thing you changed to help your baby sleep better? In a certain sleepsack, noise machine, time change, or whatever else? My LO (currently 6.5 months) was a great sleeper until 4.5 months and now wakes up all night long to eat or if his pacifier falls out of his mouth. I don’t mind waking up with him so he can eat but I’d love to try some simple things to see if they help him (and me) get better rest. Thanks! :)