Head Rush is a lot like 69 - Standing (with the exception that pleasure only goes one way); the hanging partner faces away from the standing partner, legs wrapped around the neck and arms around the waist.
The standing partner will need a sturdy back, healthy knees and strong arms; the other needs flexibility as well as a strong core. Those with back problems, be wary of strain! Here are two helpful tips: for the giver, keep your knees bent and back straight; for the receiver, keep your abdominals engaged. Finally, use proper lifting technique and make sure to exit the position slowly and carefully.
One way to assume the position is to start in 68 - Hers with his legs hanging over the side. The giver sits up and lifts as they stand, all the while holding the receiver by the waist tightly. If the receiver needs added support, the partner can use their hand(s) under the shoulders.