I need to gain weight! ( if you know about this, please help)?

Okay, so I'm a skinny 16 year old boy. I really want to gain weight as fast as possible. The comments I get make me feel so bad, I'm already low on self confidence. I've researched diets and things, but nothing has made a difference so far. I need precise instructions of how to gain healthy weight as soon as possible. Please, this would make such a difference to day to say life. I want to be comfortable in my body, and I'm pretty sure there's lots of people out there who want to be average size :-/