First, you need a sensible plan -- one you can stick with for life. you may not get one overnight... this is a great place to get information about what others are doing and the pros and cons of different plans.
Second, you have to implement the plan! Some people do everything at once and change their lifestyles overnight. Others are overwhelmed by that and take "baby steps"
Third, I think it's important to commit to this process. Obviously, you might not want to commit to one and only one plan, as that may turn out not to work for you. But you have to commit to doing what it takes... even after a failure!! (or 3!). You have to commit to planning to ensure success. You have to commit, for example, to put on those shoes and exercise, even if you don't feel like it.
And finally, keep coming here!!! This is a great source of ideas and support!!!!
My 5 C's of healthy living: Commitment to conscious control, with the understanding that choices have consequences