4 Answers

Define "best" does that mean most calories burned, or "most intimate time with your lover"?  That burns calories also, and is far more satisfying than riding a bike!

Metabolic rate = fire. The idea is to burn calories. This can be done and increased by exercise and day to day living. You can reduce the  intake but that won't fuel t he "fire" if you want it to burn faster................. 

Do Exercise. Doing regular Exercise uses up extra calories and in turn increases the Metabolic Rate.

The best way to increase metabolism rate is to start having green tea in the morning, then add little chilli pepper in your food, then have a coffee in a day, eat protein rich food, keep the intake of iron and vitamin D, exercise regularly.