I would definately recommend going through the Cambridge steps and ideally as slow as possible, this allows your body to get used to food again and also introduces carb back into your body in a controlled manner.
The whole point of the diet is obviously to maintain your new slimmer body and experience says that those who go on to maintain well are those that follow the maintenance so can't recommend it enough.
After you then finish maintenance then a lower calorie, lower fat diet is ideal for keeping that new figure.
Mike