lie on the ground, put hands uder butt, raise legs at least 6 inches off ground keeping them straight and together, do as long as you can and try too repeat 3 times. I have to tell you this GETS YOU RESULTS but it hurts really bad. but you feel great knowing you have tighter abs. good luck
Do the plank - lie face down on the floor and then push yourself up so that you're on your toes and your forearms, looking straight down - keep your back as straight as you would doing a push up, and hold your stomache tight. Most people start out doing 30 seconds to a minute of this, and go from there. I'm up to 3 minutes after a few weeks - it's hard, but it's worth it.