When I feel that way, I just try to get the most out of a single injury that is as small as possible. I have mild hemophilia, so a small scab will bleed a lot. Typically I will pluck the hairs on my ankles out, until I get a few little scabs from it, then pick those scabs. I guess it's still technically self-harm, but at least I've toned it way down from the days of cutting up my limbs.