Will my plan work?????

I am currently a size 12 and would like to be a size 8 by time I get married in October. I have myfitnesspal app on my iphone, I am sticking to a 1200 calorie per day diet and doing exersize on my Wii (the muscle and yoga workouts as well as advanced stepping). I have just quit smoking so plan to use my stepper for 15 minutes twice a week once my lungs can handle it. Do you think my plan will work? I am also watching how much fat is in the foods I eat. Is there anything else I can do or should do? I am a busy mum of three, I can't go out running and can't afford a gym. It's not just about being thinner for me, I want a more toned waist too, I am also using a toning belt three times a week for 20 minutes.