Bedtimes

Hello! My daughter is nearing the four month mark and is consistently going to bed around midnight. I have tried beginning the routine a little earlier (10pm) to start, but I just don’t seem to be having any success. She usually sleeps 5-6 hour intervals but there has been times she has slept 9-10 hours when she fell asleep earlier. Ultimately, I’d love for her to be in bed by 8pm! Any tips would be greatly appreciated :)

to add: I don’t necessarily have her on a strict feed/activity/nap schedule.