1) Draw-in
The easiest way to work this muscle is to do draw-in exercise. Sometimes, it is called pelvic tilt or ab set or iso abs. This is done by laying on the back with knees bent at around 90 degrees and trying to draw the belly button in towards the back. Or you can try to make the back flat against a table or floor. Sometimes, it is easier to do when you have a hand of someone's between the lower back and floor and try to press the hand down. You should not hold your breath or other body areas like neck and arms should be relaxed. Try to hold this position for 10 seconds and repeat 10 times to start. It may not as easy as it looks to do this exercise the right way.

