Go straight to the main issue, here the two great exercises that demonstrate how to build muscle quickly. All individuals skinny and thin, this is the time to get back his confidence:
Get some exercise weights that are light lead. Without moving your back, lift both weights gym on his head. Open your feet slightly and then your palms facing inward, put them up on their sides. Bring the weights in a gym up near their ears and the lunge them. During this process, keep your back on the floor and do the 90 degree angle with your front leg. Gym weights should be pushed upwards then turned out with their palms. Almost remember, have your spine in the upright position otherwise you get, back pain. If you follow this step correctly you will feel the difference before and after this is resolved.
Take a drive up lying on the floor with your forearms on the upright position. Make a fist and then keeping your toes 90 degrees. Keep your position by placing one arm behind your head for 5 seconds. Repeat this process with the other arm as well. This way you not only build your muscles fast but you can also train your ABS.
If you want to know to build muscle quickly, and follow the above process repeats again and again. You will surely result in a few weeks. Be on time and not drain your self and enjoy their resolves.