It is highly not recommended for people to place drugs in their system, especially with needles. Shooting up is dangerous because it can create an infection, HIV, AIDS< uncontrolled bleeding and other things even death. A sterile needle is the most important thing to use. Do not share neeldes, because you are going to get every possible disease that person ever had from blood. The skin has to be wiped with a disinfectant, such as rubbing alcohol or Iodine. I don't know what you are trying to shoot, but if it is Intravenous, then find a vein and Place the needle almost parallel to the vein. If you are trying to inject for medicines or diabetes, then subcutaneous injection is the best choice. The needle just goes right under the skin (not too deep). Intramuscular injections are performed in the Deltoid muscle. The needle goes straight in, almost perpendicular to the skin. You have to aspirate the needle before injecting the medicine. If you aspirate (pull back on the plunger) and you see blood, that means that your needle has entered a vessel, in which case you will end up inadvertently injecting into your bloodstream. In this case, back the needles a little and re-aspirate until no blood shows on the needle. Then you can inject into the muscle.