Getting started with your Polar H2 heart rate sensor is easy. First, make sure you thoroughly wet the electrodes on back of the strap with water and snap the transmitter into place. Then wrap the strap around your chest. Adjust the strap length to fit snug, but comfortable. Check that the moist electrode areas are firmly against your skin and that the Polar logo of the transmitter is in the upright position. When you are finished with your workout detach transmitter, rinse the strap with water and hang dry.