I was so motivated and excited during my first Master-Cleanse in April I bought the Hip Chicks Guide to Macrobiotics, scoured the shelves and internet for supplies and ended up doing really well for about the first month. I am eating more vegies since the cleanse and hardly any dairy or meat, but still am indulging my sweet tooth. It is very easy to go back to our "old ways" so write down your plan, post it prominently, avoid the 'I'll just have it this one time...' dialogue.
Also, make exercise a part of your life. This is just the beginning of the journey toward better health. Healthy, whole foods and exercise are key in living well. So that's my 2 cents. Good luck!