Hi Dr. Tony here! If you give yourself injectionstestosterone, estrogen, insulin, peptides, or B12these are 3 of my favorite tips to make them almost painless. Tip 1: Insert the needle quickly, then Administering a B12 Injection Safely and Professionally How to Safely Self Inject a B12 Shot Perfect for IV Med Spa Clients! , Steps to give yourself an intramuscular shot:, 1 Prep Your Supplies: If youre drawing up B12 yourself, attach a needle to How To Give Yourself Vitamin B12 Shots (with video!)