When it comes to healthy behavior changes, most people want to go big. People like drama. Also, most people have very low levels of patience. (If I were looking at you, you could tell me that I'm the pot calling the kettle black, but I'm just generalizing.)
Anyway, the problem is that habits did not develop overnight, so it's unreasonable to expect to be able to change them overnight. Let's say there are five things about your diet/lifestyle that you'd really like to change. Let's further say that you are currently doing more or less the opposite of what you'd like to be doing, it would be overwhelming to completely reverse all five things at once. My personal preference would is to make a small change in a few areas, or even just one area. This is particularly helpful if you have a lot going on in other areas of your life (jobs & kids come to mind!).
Here's a personal example: before I had my baby a year ago, I exercised every day, including hour-long walks with the dog, yoga classes, and truncated strength training. I did this right up until labor & delivery! I actually even did fairly well during my maternity leave - short walks most days, sometimes stretching & the rare yoga class. I also cooked most of our meals from fresh ingredients. Since going back to work (TEN months ago), there have been altogether too many processed meals. We fell into a rotation of frozen pizza, frozen family entree, spaghetti (with a vegetable side!), snacks (chips/crackers, hummus/veg/pita). I told myself throughout that when the baby started eating solids, I'd have to do better. I was a little behind that goal, but I have been doing much better the past several weeks. Frozen pizzas and Stauffers family meals are the exception not the norm. In the past 3-4 weeks, I have been serving fish once weekly. I already eat fish at least twice a week - I have a Lean Cuisine for lunch nearly every day and choose the seafood options just under half the time. It was important to me that my daughter develops an early appreciation for a wide variety of healthy foods. In the area of activity, I made a point to always take the stairs when changing floors at the hospital; I also parked quite far from my office. I still do. For the past few weeks I've made a point to take a walk on each day of the weekend. This past week I added to that 1-2 sessions with our Kinect Fitness.
See ... 2 of my themes are present in this story. 1 - I've done tiny things. I feel better. My weight is stable despite stopping breast feeding a few weeks ago (which was burning something like 700 calories daily!). 2 - I did not stop with the first changes I made. Once the initial improvement was old hat, I upped the ante.
More examples will follow, both personal & specific ideas for changes you can make & why you should consider them. Perhaps at some point, I'll even figure out how to put up pictures!