1.Determine the meal time, make sure you eat within 30-45 minutes after the injection. 2.Prepare the alcohol swab, needle, insulin pen and insulin, note that the insulin pen and insulin must be the same manufacturer’s product to avoid mismatch. 3.Check the insulin dosage form once again. 4.Check the appearance of insulin carefully. Medium-acting and long-acting insulin or premixed 50/50 and 70/30 insulin are uniform-looking suspensions, which are like milk after shaking gently. If there is sediment at the bottom of the bottle after shaking gently, small lumpy objects precipitated or suspended in the liquid, and a layer of “frost”-like objects adhering to the wall of the bottle, it cannot be used. Then, choose a suitable injection area: commonly used insulin injection sites include the outer part of the upper arm, abdomen, outer thigh and buttocks. Take 2 square centimeters as an injection area, and each injection site can be divided into several injection areas, and injection area means that each injection should be in one area. Each injection site should be rotated instead of several injections in one injection area. The abdomen is the preferred site for insulin injection. The insulin absorption rate in the abdomen can reach 100%, and the absorption rate is faster and the subcutaneous tissue is thicker, which can reduce the risk of injecting into the muscle layer and make it easiest to self-inject. Next, the injection: Before each injection, it is necessary to check whether there is enough dose of insulin. When injecting, the left hand gently pinches up the skin at the injection site, the right hand holds the insulin pen and sticks the needle directly into the pinched skin, pushing the liquid, after the injection is finished, the thumb is removed from the dose knob and the needle stays under the skin for more than 10 seconds, then the needle is pulled out and the eye is pressed with a dry cotton swab for more than 3 minutes. After the injection, you should put on the inner needle cap, screw down the needle, discard the discarded needle, and put back the pen cap. Generally speaking, unopened insulin refills can be stored at 2℃-8℃ (in the refrigerator), and refills loaded into the insulin pen after opening can be stored at room temperature (<25℃) for about 1 month. Patients should pay special attention that insulin refills should not be frozen or exposed to sunlight.