Medication can be very effective, although it had no effect on my skin picking. I've just had to be very conscious, and any time I get the urge to pick I try to find an activity that keeps my hands busy.

For a while I actually put a rubber band on my wrist and just snapped myself any time I had the urge to pick, and eventually the urges subsided a bit. My picking was primarily focused on my hands and forearms, so I started trying to pamper them a bit, giving myself manicures and applying lotion multiple times a day, etc. Another thing that helped was fake nails, they make it really difficult to effectively pick anything!

I also hid the things I use to pick, no more razor blades or exacto knives in my bathroom, and nail clippers are only for use in trimming my fingernails and toenails. Out of sight, out of mind!