To use the Wahoo TICKR Fit heart rate armband, first make sure the battery is charged. You can use the included charger to charge it. Once charged, adjust the band to fit your forearm comfortably. Turn on the armband and use the Bluetooth or ANT+ feature to pair it with your fitness app, smartphone, GPS bike computer, or watch. When you start your workout, the armband will automatically start tracking your heart rate and calorie burn. After your workout, you can view the data on the paired device. Remember to keep the armband dry as it is water - resistant but not fully waterproof. Also, don't expose it to extreme temperatures. To maintain it, clean the band regularly with a soft, damp cloth to keep it hygienic and in good condition.