A huge thing for me is that I need to have a heat pack with me, especially since it helps a lot of my abdominal pain—then, once that's satisfied, I love binging YouTube videos or reading a book while curled up with a blankie :)
Back when I had periods, my favorite thing to do was heat up my huge pink bunny warmie (microwavable plush), and curl up on the couch to watch true crime documentaries and dramas on Hulu with a nice cup of raspberry tea!