How to Give a B12 Injection: Step By Step Instructions B12 injections UK How I give myself a vitamin injection Vitamin B12 Injections: What You Need To Know B12 Injection sites + How to use B12 Shots Safely How to self administer subcutaneous B12 injection., 1. Withdraw proper dosage from vial into an insulin syringe, 2. Clean site of injection (abdomen or other proper site), 3. Pinch the skin where you Vitamin C and B12 Injection Techniques