1) Eat as few animal products as possible. Many people eat meat at every meal. This is not essential, and it isn't healthy for anyone. When Gandhi became deficient on a vegan diet, he went back to drinking a glass of goat's milk every day. A friend in China has been vegetarian her whole life. Every day she eats two eggs for breakfast, and doesn't eat any other animal products for the rest of the day.
2) Consider eating eggs or dairy instead of meat. Eggs and dairy do not require the killing of an animal, and they provide much of the nutrition that may be more difficult to find in plant foods (such as B12, Omega 3 and iron).
3) Avoid some of the cruelties found in factory farming by eating eating free range. "Free range" animals have much more freedom than animals trapped in factory farming. Also, free range animal products often have twice as much nutrition than factory farmed animal products.