I need advice on helping my friend lose weight!?

Walk for 45 minutes a day. The reason we're suggesting 45 minutes instead of the typical 30 is that a Duke University study found that while 30 minutes of daily walking is enough to prevent weight gain in most relatively sedentary people, exercise beyond 30 minutes results in weight and fat loss. Burning an additional 300 calories a day with three miles of brisk walking (45 minutes should do it) could help you lose 30 pounds in a year without even changing how much you're eating.