There are three main types of injections. They are intravenous, intramuscular, and subcutaneous injections. Of this, only the second and the third are used to administer anabolic steroids. The last one is not even recommended. Here is more about the three kinds of injections.
Anabolic steroids should never be injected intravenously. In intravenous injections, the liquid is injected into a vein. These injections are usually given to the radial artery or the brachial artery of the arm. Anabolic steroids that are meant to be injected are usually based in oil or water. If it is introduced into the body intravenously, a pulmonary embolism may be induced, which leads to a heart attack.
Anabolic steroids are meant to be given intramuscularly. In this process, the steroid is injected deep into a muscle. The muscle then releases the steroid slowly into the blood, through small veins and capillaries. A relatively large volume can be injected into the body by this way. It is also one of the safest ways to inject any medication into the body. Some muscles can even tolerate up to 5 ml of the anabolic steroid injection, whereas normal muscles can hold nearly 3 ml without any problem. But note that you should rotate the injection site and maintain a gap of 7-14 days before you re-inject into a site again.
Subcutaneous injections are usually water based. The pin penetrates the first two layers of the skin and then the fatty layer or the subcutaneous layer. Hormones such as insulin are usually administered subcutaneously. Sites for subcutaneous injections can only hold low volumes of liquids. So while anabolic steroids can be subcutaneously injected, this method is not recommended.