The correct way to tie a blood pressure strap is to tie the cuff to the upper arm, about 2 horizontal fingers from the elbow socket. The standard method of tying the cuff of a blood pressure monitor is to wrap the cuff around the upper arm of the body, with the lower edge of the cuff about two horizontal fingers above the elbow socket. In addition, the cuff should be tightened so that the upper arm can rotate inside the cuff, but not so tight that one or two fingers can be inserted. In addition, it is best not to have any clothing inside the cuff, otherwise it will affect the accuracy of the blood pressure measurement results. It is important to note that the strap, the blood pressure measuring device, and the heart should be at the same level, and then the stethoscope should be placed in the elbow socket at the brachial artery pulsation for measurement.