Need Help Bulking Up

Hey sythe members, I just turned 15 years old , I am 6 foot tall, 112-115 pounds and i need help gaining muscle. I would like to know exactly what should I do to gain muscle. Due to my fast metabolism, it seems like I cant do any workouts that involves upper body strength. I want to play basketball in high school but from what iv'e heard I must be bigger in size. What do you guys think I could do to gain muscle? Also, i would like to know from people either that have experienced this or people that are 100% sure because I don't want to do anything wrong.
Thanks in advance.

 

5'11 145 here, been bulking up recently and have noticed some progress.

Protein powder after workouts help.

Lift heavy, as in you find it hard to do 10 reps.

Limit your cardio and eat a lot more then you're used to eating.

 

increase lifting weight, decrease reps, increase diet, or whatever u eat daily by 500 calories, don't go to big ul'l make more fat gains then muscle.

 

zyzz is right increase it with 500 but if you are a skinny guy go ahead make it 750.

 

just eat alot.