Set your rings appropriately for your level - higher to make the exercise easier, lower to increase difficulty. You may bend your knees if necessary, but keep your hips extended & glutes engaged.
Begin by retracting your shoulders, then pull the rings outward, flexing your elbows to 90 degrees.
From here externally rotate your shoulders, try to drive the rings up and back.
Maintain your 90 degree elbow position and try to isolate the rotation to your shoulders.
Pause at the top, squeeze your mid back, and return to the start with control.
Repeat for repetitions.