How do I increase muscle?

Hannelore F.
Low reps, high weights
Diet of protein, fiber, and carbs (your essentials.)
Cardio
Shed weight first, tone up (low weight, high reps,) bulk up.

Paula E.
Adjust your nutritional intake to include more calories and more protein. Make sure you’re staying hydrated and not pushing yourself too hard. Good luck!

Eric Y.
You workout hard and regularly.
Do muscle training and cardio. Do not forget stretching.
Eat healthy diet with lots of protein.
Sleep well.

Fanny O.
This entirely depends on what you do to gain it and also on how easily you gain it normally.
Outdoor work such as chopping wood, or doing some gardening and carrying helps to build your working muscles.
It also helps to aim for eating high protein food, and to generally lift either heavy weights or to body weight work out (don't forget to stretch or do cardio either). To just eat a salad or something lean wouldn't help you much to gain that muscle, instead aim for eating some eggs and bacon with toast plus a fruit salad to get a full feeling. Don't ditch carbs, protein or healthy fat when you want to gain, if you do you will only reduce.

Eric U.
Eat enough protein for your body to develop and excersise. The type of excersise differs from one type of muscle shape to another. mainly you will have to go to the gym, do fitness or any type of sport will help you. You also should train with a personal trainer to help you along the way.