The sides of my thumbs are calloused and permanently red from me picking at them with my index finger since I was a kid. It’s very easy for me to pick my fingers to bleeding and not notice until it feels wet or stingy. - https://twitter.com/dustychipura/status/1280562345270337537">https://twitter.com/dustychip...

As Dusty mentions later on, my picking comes from an incessant need to make things smooth. I am CONSTANTLY rubbing over my fingers, toes and face as a stim, and when I find anything out of place, I pick, pull and scratch. I don’t always notice before I’m bleeding/in pain. -

2 things that help (not cure) is having nailclippers easily accessible for preventative maintenance, and oil cleansing out the annoying hard grains of sebum when I shower.
I legit believe this may in part have developed from having other stims like thumb sucking suppressed. :(