How do you get buff when your a kid?

you can get buff by lifting weights and having a well balanced diet use proper form because if you don't you can injure yourself. and if you can, do between 8 and 10 reps then go with a lighter weight. if you're 11-13 years old, start with 5 lb. dumbells and eventually build up. i recommend starting with 20 min. per day lifts, non-stop.