I post three times a week, Monday, Wednesday and Friday. I based this off of other YouTubers in my genre and how successful they were. In my research I noticed the ones that only posted sporadically didn't seem to have a "community" of followers.
It's not easy, I too work full time, have four kids and I do craft videos so I have to "come up with" three crafts a week that aren't tired!
I just think a regular schedule has worked wonders for my channel. I also know my community likes the schedule. I even have to announce if I'm gonna miss a day or they will be checking on me, which I think is wonderful.
Look at your YT mentors and see what they do and try it out for yourself. Good luck!