When I am driving and there is a shadow of say, a tree in the road, I try to make the shadow to light ratio that each wheel goes over the same. so like if there is a tree or house or building or other cars parked on the side of the road, I am all over the place trying to get the other side of the wheels to go over the same amount of shadow. I do the same thing with puddles too. and walking on the sidewalk.
I do the volume thing, but just with evens.
I also do the foot drag thing. or muscle twitching. or biting my lips/tongue. or tapping fingers or toes or whatever. like if my foot drags on the floor I have to do it twice with the other side and then once with the first side. Or if I flex my calf or quad or whatever I do that again to make it symmetrical. It goes left right right left right left left right and I do that a couple times until it feels even.
Then walking on sidewalks or tiles, if I step on a crack with one foot, I have to step on a crack in the same way with the other foot, then do it again in reverse, then do all that again in reverse. like that ^ stuff. same with different color tiles and rugs or whatever.
There's a lot more stuff I cant think of right now. yes I have OCD.