The fastest way to build muscle is to exercise one body part per day of the week. You must keep the right diet and maintain the correct rest periods. This is the triangle of success: exercise, diet and rest. Let’s assume you have a Monday to Friday job. If you don’t you can adapt the sample timetable I will give below to your lifestyle.
The first step in muscle building is finding a good gym. This is one that is open at the times of day you need and has equipment that is not broken or damaged. It does not have to be a shiny new fancy gym as these tend to be very expensive. The gym near your house will probably suffice.
Monday: Legs training. Do 3 sets of 10-12 reps for each exercise. Start with 20 minutes on the stationary bicycle to warm up. Then move on to 45% leg press, seated leg extension, lying leg curl, weighted squats and finally a calf exercise.
Tuesday: Shoulders. Do 3 sets of 10-12 reps for each exercise. Do barbell shoulder press, cleans, upright row and lateral flyes. Finish with abdominal and lower back exercises.
Wednesday: Chest. Do 3 sets of 10-12 reps for each exercise. Do dumbbell or barbell bench press first, followed by incline press and decline press. Alternate so one week you do all dumbbell exercises and the next barbell exercises. Always finish with flyes or some exercise that will open up and stretch the chest. Finish with abdominal and lower back exercises.
Thursday: Back. Do 3 sets of 10-12 reps for each exercise. Do pulldown to chest, overgrasp and undergrasp heaves, and seated rows with a narrow grip. For the heaves do as many as you can as 10-12 reps is difficult for most people. Finish with abdominal and lower back exercises.
Friday: Arms. Do 3 sets of 10-12 reps for each exercise. Use varying biceps and triceps exercises. If you still have the energy after Thursday’s back exercises (which also work the forearms), do additional forearm exercises. Finish with abdominal and lower back exercises.
Start each session by stretching the muscles you intend to use. This is to warm up the muscles. On the first exercise do 2 sets of 14-20 reps without any weight. This is to further warm up and avoid injury. Between each set stretch the muscle you used. You should know which one it is because at the end of the set it should be burning.
Take a sip of water and add a little extra weight so that you do the next set with more weight. Your entire break between sets should be 30-45 seconds at most, and between exercises 1-2 minutes at most. However the 30-45 second breaks are ideal. When lifting the 10-12 reps use weights that will make you really struggle and push yourself. When lifting/pushing the weight do it fast but in correct form. At the same time breathe out fast and hard through the mouth. Lower the weight and inhale slowly. And repeat.
At the end of each training session drink a protein shake with carbohydrates and with as little sugar as possible. This should be with approximately 30g of protein. Also take a teaspoon of magnesium to avoid sore muscles the next day. If you do your exercises hard and properly you will still feel sore muscles but the magnesium will greatly decrease the pain.
If you want you can drink creatine as a supplement. Creatine fills your muscles with water so that you can lift heavier weights. You are likely to gain about 5kg of water weight within the first week of drinking this. Remember that once you stop drinking creatine you will lose the water weight and tighten up. However it can be good for quickly building muscle.
Eat a full meal as soon as possible after training. Eat a large meal every 4 hours and have a snack whenever you feel hungry between meals. Make sure to eat plenty of protein (meat, fish, beans etc), carbohydrates (rice, bread, oatmeal etc.), vegetables and fruit every day. Do not eat unhealthy snacks as they do not burn well during training, rather will be converted to fat. This is especially true if you exercise in the mornings and snack in the afternoon or evening.
Make sure to sleep 8 hours each night so the muscles can rest and regenerate. Keep stretching all muscles that feel sore or tight throughout the week and weekend. Breathe deep while stretching and feel the muscle stretch further with each exhale. Drink plenty of water after your training and throughout the day. Do not stick to 2 litres a day; rather drink as much as you need. It will always be more.
Remember that this is strictly to build muscles both in size and strength. After a few months when you reach your desired physical size you should stop eating carbohydrates, taking creatine, and drinking protein shakes with carbohydrates. Drink non-carbohydrate protein shakes and stick to eating protein, vegetables, fruits and nuts. Good luck!