The best diet advice when following the Traffic Light plan is to think of trying to consume foods in a very natural state.
You want to eat foods that come as closely from the ground as possible so this will include things such as fruits, vegetables and nuts.
By following this diet advice you won't have to pay quite as much attention to ensuring you are following the 'list' of foods they provide since you know that you'll be matching closely to what is called for.
Another piece of diet advice that followers of this program should remember is that it will be very important to look for 'hidden' ingredients in their dishes. For example, while a stir-fry may seem like a perfectly healthy dish and in line for what is called for on the plan, if it is made with a sauce that contains a high amount of sugar, it isn't exactly what you should be going for. You must be sure to read the ingredient listing on many of the packaged foods you consume to ensure they do not contain a lot of processed carbohydrates or saturated fats.
Finally, just remember that if you do experience a small set-back, try and get back on right where you left off. It is not the end of the world if you are really, really craving a red food and you give in and eat it. As long as you watch the portion size you consume and don't go overboard and allow yourself to start binging on a great deal of red foods after giving in to the one, it won't make a large dent in your overall progress.