Lie on your back with knees bent, and extend arms down your sides with fingers pointing toward your toes. Gently exhale and stabilize your core muscles. Cross your legs at the ankles and slowly bring your legs back and up “crunching” your abdominal muscles. Inhale and slowly lower legs to starting position. Repeat.
Before performing any abdominal exercises, make sure to check your abdominal muscles for separation – How to check for Diastasis