Commonly used insulin injection sites are: outer upper arm, abdomen, outer thigh, buttocks, with 2 square centimeters as an injection area, each injection site is divided into several injection areas, and the injection area means that each injection should be in one area. For each injection, the sites should be rotated and should not be injected in one injection area several times. The rotation of injections can be based on the following principles: 1. Choose the left and right symmetrical site for injection, and rotate the injection left and right symmetrically. When the rotation is finished, change to another left-right symmetrical site. For example, left upper arm → right upper arm → left lateral thigh → right lateral thigh → left buttock → right buttock → left upper arm …… cycle alternation. 2, the rotation of the injection area within the same injection site should be regular to avoid confusion. 3, different parts of insulin absorption from fast to slow, in order: abdomen, upper arm, thighs, buttocks. 4.If the time of occasional meals may be advanced, choose the abdomen for insulin injection, and if it is delayed, choose the buttocks for injection.