Has anyone found anything that helps with the mood swings before their period?

Lately I've noticed that the few days before my period are much harder emotionally than they used to be. I'm more irritable, little things get to me, and I generally feel like I'm not quite myself.

I've been trying to get better about sleep, eating regularly, and keeping track of when it happens, but I'm still looking for other things that might make that part of the month easier.

What has helped you during that time? I'm trying to find a few things I can realistically stick with rather than completely changing my routine every month.