There is no easy answer here. Firstly there is no such thing as spot reducing. If a person is overweight, the fat will be in different areas according to the individual,calfs,thighs,stomach etc. So diet is the number 1 for fat reduction. Strengthening the stomach muscles will help however by giving you a firmer line. I cant set a routine because it has to fit your capabilities so lay on your back hands behind your head and your feet held by someone or under some furniture see how many times you can comfortably sit up. If you cant do any then help yourself by throwing your hands forward and work your way up to sets of 12 of which you do 4 of them. When they get easy then the hands go behind the head and eventually you can try without your feet being held. But the main thing is you keep within your capabilities, no straining.good luck.ex-trainer