Hey ladies, I think it might be time to drop another nap, but I don’t know how to time it. How did you do it?

My baby nurses every three hours during the day and we would do the eat, play, sleep cycle, meaning he would nap every three hours, also. I am a schedule person and it worked really well for him until this past month. Every nap time and bed time he is far too awake and fussy. It’s making having a babysitter difficult, so I think he might need to drop. Thoughts? Articles? Thanks.