Sit on the floor with your legs straight in front of you. Keep your back as straight as possible, and fold forward from your hips. Pull your chest toward your knees without rounding your lower back. Hold the fold, then return to the start. This is essential for L-sits, V-sits, and handstands. Good compression means you can lift your legs high without arching your back. Practice it daily. It's the difference between a good and great L-sit.