Weight training is the most important part when trying to put on muscle. You need to have workout splits which allows for you to workout different muscles on certain days because you do not want to hit the same muscle during back to back workouts. This is because your muscles need time to recover after the workout. I like to use a split that consist of working out two different muscles each day over a set of three to four days. There are multiple ways to go about weight training and many ways can be effective. Using the correct form is extremely important when lifting weights because you do not want to get injured while lifting heavy weights. Also, doing the exercise correctly will allow for you to have a more productive workout.
When trying to put on weight, eating the correct amount of Carbs, Protein and fat is the key to gaining weight. Using a calorie counter to find out how many calories you need to consume is ideal because whatever that number is, you have to add 500 calories or even more to that number. Easy ways to get extra calories in, is eating a protein shake that consist of 1000 calories or even more. Eating healthy food is also important because you do not want to fill your body with bad foods that will cause you to have less energy throughout your day. In order to gain muscle, you have to eat protein. Protein consumption can be calculated by finding out how much you weigh, and then eating that exact amount (give or take a few) in grams of protein.
Sleep is also important when weight training and trying to put on weight/muscle because your body needs time to recover. During your workout, the muscle actually breaks down. Sleep and rest help build the muscle back up. It is recommended to get at least 8 hours of sleep each night for maximum muscle recovery.