I guess this is less a rec, more just what works for me.
When I'm in really busy eras I have a night where I actually handmake a few months worth of calendars (like literally with a marker, and a ruler, and heavy paper). I hang them up on the wall, and I just start filling them up.
When the busy-ness fades I take the months down and keep them. Also cool because you have an analog record of what you did for a while.