My First day...

I am starting today.. I recently had my second child and really need to lose some weight. So I am here hoping I can stick to it. I normally fall off the diet wagon after a week but I really want to lose 45 Lbs by 2013 for my wedding. Both of my children (17 months apart) were born by a csection so if any of you have been through it if you could tell me anything that helped you get back into shape please let me know..