The best time to inject glargine insulin is subcutaneously at bedtime, i.e. 9-10 pm. Glargine insulin is an analogue of long-acting insulin and can act for up to 30 hours without a significant peak in action. If it is not convenient to inject before bedtime, you can also choose to inject in the morning, or choose a fixed point in the day for subcutaneous injection, which is not related to whether or not to eat, but mainly to maintain the stability of basal blood sugar throughout the day. The abdomen is the preferred site for injection, because the abdomen has a better absorption effect. When injecting, avoid the area around the navel and inject in the lower part or side of the navel, one palm away from the navel. Before the injection, we should pay attention to the disinfection of the skin, inject slowly, and the needle should stay under the skin for 10-15 seconds after the vertical skin injection in order to fully absorb.