Keep mementos and signposts of your journey to success.
I recently met someone who lost a good deal of weight who told me that he had kept nothing to remind him of his overweight past...not even photos. I believe he was making a mistake by doing that. Whilst I understand his desire to expunge the past from memory, the danger is that he may forget the importance of his achievement. I keep quite a few things to help me stay excited about keeping the weight off.
I have a pair of pants that I step into occasionally and use to illustrate to others the achievement. Stepping into them is a surreal experience and yet it enforceable shows me that I was literally twice the size I am now.
During my weight loss journey I constantly wore a beanie with the word "reality" on it. It was a challenge to me to get real with my God, my family and above all - with myself. I still wear that beanie today. Each time I look in the mirror and see the word "reality" it spurs me to stay real to the course I've chosen.
I have my "fat" photos close to hand (on phone, ipod and laptop) ready to show anyone who is interested. Each time I show them...I show myself what was and what shouldn't be again.
I have other mementos and signposts. I wear a superman logo on a t-shirt and get a lot of flack from strangers doing so but what they don't know is that wearing it reminds me to be my own hero. My weight loss book is another. Not only does it keep me accountable for today but it also signposts my past success and shows me that future success is there for the taking.
Find items that you can use as useful symbols to physically remind you of the past - and the success for the future. We are creatures of our senses. Engage the senses will aid your memory and resolve.
Now: keeping it off for life!