How to gain some weight?

Lifting is the fastest workout to gain weight, and you need to make sure that you're eating a lot of calories before and especially after lifting. Running a lot can actually hinder your ability to gain weight since it promotes slow twitch muscles. Most people eat more protein than they need, but make sure that you're getting enough protein in your diet. Basically, you want to eat as many healthy calories as possible (ex. pasta is good for this, but if you layer on a ton of fatty alfredo sauce, you aren't going to gain healthy weight). Fruits and vegetables are good for nutrients, but won't help much with gaining weight (you'd have to eat a ton).

Would like the answer to that myself!