It is very useful to many people to deal with their cravings to self harm, through the use of elastic bands.
All you need is an elastic band that you can wear around your wrist all day long. What you do is to stretch the rubber band and “ping” it against your skin in the area you usually self harm.
This method works because, whilst it does hurt, it leaves no permanent mark. When you feel the pain of the rubber band and see the red mark that it leaves, your brain associates this with having satisfied the craving.
Please note that this is most effective if you follow your usual routine (or ritual) for when you are self harming, but replacing your implement with an elastic band. This will make your brain think that you have done everything that you normally do and calm down as it thinks you have self harmed.