A) Eat 6 small-ish meals a day, spread out in 2-3 hour increments. This will jumpstart your metabolism, and start you into burning mode.
B) Eat clean, and watch what you eat. It's cliche etc, but I'm assuming the only reason you want metabolism is to help you lose weight. If you start the correct method of dieting/losing weight, you will automatically gain that metabolism as a side effect. They go hand in hand.
good diet = good metabolism
bad diet = bad metabolism