Secure an appropriate strength resistance band to one of the rings. Leave a slight slack in the band, and thread it through the other ring, securing it in place by gripping over it.
Now proceed to pull yourself into an inverted position. You may bend your knees to make it easier to get to the start position. Once you are upside down, make sure to get into posterior pelvic tilt (tuck your tailbone), protract your scapula, compress your core and create full body tension. Then start lowering yourself, maintaining tension. Try to reach a horizontal body position, adjust the difficulty by using a heavier or lighter band. Hold for time.