I like to fold paper receipts into pointy ends and use them to poke, stroke and generally pick at my fingers (usually my index), the good thing is that I can do it discretely in my pocket or under a table etc.

Foot tapping/bouncing too, and I also like to stroke my hair to remove dead strands and twirl the ends. Recently I've started to enjoy making a popping sound with my lips, but mainly when I'm alone as it's audible

I also have resurrected my childhood/teenage/early 20's blanket that I like to smell (I don't know if that's a stim exactly, but I enjoy sniffing it, and it feels comforting when I do this)