Step 1: Cut back your meat and dairy intake by 50%. Replace it with vegetables (including lots of leafy greens), fruit and whole grains. You will probably start losing weight and noticing some health benefits. Maybe you want to hang out in this stage for a while and enjoy some weight loss and the huge impact you have made on the well-being of animals! Oh, and if you really want to lose weight, cut back on the cheese. If you are feeling up to the challenge, you can try cutting back on the refined grains and sugars too--replacing them with whole grains and fruits.
Step 2: If you want to experience more healthy impacts, probably the most effective step to take is to cut out dairy. The growth hormones in dairy (even in the non rBGH fed cows) and the animal protein (casein) are great for growing cancer cells (see The China Study). And dairy contributes to a host of allergies and auto-immune diseases. Finally most of us are lactose intolerant to some degree and don't know it. Once you get rid of the dairy, watch that indigestion disappear! And weight will continue to drop off when you cut out this high fat food (yes even the "low-fat" varieties). Just add in more of those lovely vegetables, fruits, and whole grains to replace the dairy. Oh, at this stage you probably want to try cutting down on the refined grains and sugars (replace with whole grains and fruits).
Step 3: Now if you really want to improve your health dramatically, you just have to take one more step and that is cut back even more on the meat. If you can cut down to just a few servings a week, now most of your diseases will go away. No more heart disease, diabetes, autoimmune, allergies (see this link from Dr. Fuhrman's website and the linked articles off there on the right panel). No kidding. Replace with, what else, vegetables (lots of leafy greens), fruit, whole grains, and nuts and seeds (1-2 oz per day). Oh, and pretty much cut out the refined grains and sugars except for special occasions. But don't worry, you can still eat some delicious dates and dried fruit and lovely berry/banana ice creams and all kinds of great desserts. Ta-da!