So, because of my ADHD, just one thing doesn't cut it.
But, whatever I do, I try to keep one thing in mind. Giving myself grace. Before I found out I had an anxiety disorder, I was super hard on myself. It took time and patience to apply the grace I give to others to myself, and sometimes it's a struggle, especially on days when I spiral.
But, some things that help nowadays are reading (both audiobooks and physical books), crocheting, and playing D&D.