Like the 2nd poster says...upper outer part, and certainly not in fatty tissue. It is meant to be injected IM=Intramuscular for proper absorbtion. If you are unsure just look here ...there is a link on pm..."How to do injections"
Agree with the rest. Intramuscular is the key word. Inject slow, rub it out, apply heat, whatever works for you to reduce soreness but I wouldn't suggest fatty areas IMO. Sometimes aas use is just a pain in the arse!