Mental health professionals often advocate minimization strategies and grounding as alternatives to self harm. These techniques do work for some people but research suggests others find them most unhelpful. It offers short term solutions, helps some people but does not reduce the urge.
For example, snapping rubber bands on yourself, painting red lines on your skin, holding ice, running your hands under cold or warm water,eating sour or spicy candle, squeezing a stress ball, punching pillow or cushion and screaming into a pillow.
Safer self harm practices such as sterilisation of self harm tools. Treating injuries immediately. Only self harming when you have someone you trust with you. Reducing self harm intensity ie scratching yourself instead of cutting
The afore mentioned techniques might help you when your not qiute ready to stop self harming but want to stay safe as you begin exploring alternative coping strategies.