Take a supinated grip on the ring and hang actively in a hollow position. (Shoulders depressed, leg together, feet slightly in front, core engaged)
Keep your legs straight, hinging only at hips. Compress your core, pull down on the rings (with straight arms) engaging the lats, & raise your toes to your hands. Stay tight and try hard to restrict upper body movement.
Squeeze at the top, and slowly control back down.
Repeat for repetitions.
Keep the arms straight, limit movement from your upper body. Don’t arch your back at the bottom, keep tension on your core throughout.