Anyone who wants to gain muscle must train the neck so that the head region is proportional to the others. Also, doing certain exercises creates the "impression" that the person is fit, as the neck is one of the most visible areas of the body. Start with simple stretches, take it easy so you don't get injured, and gradually increase the intensity, endurance, and load to get where you want to go.
Steps
Part 1 of 3: Getting Started with Stretches

Step 1. Move your shoulders in circles to relax
With your feet squared on your hips, lift your shoulders toward your ears, then return to the starting position in a circular motion. Do this several times in each direction fluidly and without straining your body to feel the relaxing effects.

Step 2. Touch your chin to your chest to stretch the back of your neck
With your back straight, lean your head forward as far as you can-preferably until your chin touches your chest. You can use your hand to apply some force to the back of the head and extend the movement, but be careful. Stay like this for about 15 seconds.

Step 3. Tilt your head back to stretch the front of your neck
Stand up straight with your back straight and feet in line with your hips. Relax your shoulders and slowly tilt your head back until your face points to the ceiling. Then lift your chin as far as you can to stretch your neck. Stay in this position for 15 to 20 seconds.

Step 4. Turn your head to the side as far as you can for a few seconds
This movement stretches the muscles used to rotate the head horizontally. Turn it to the left as far as you can go - using a little hand force to extend it even further. Stay like this for 15 seconds and then slowly return to normal. Finally, repeat on the right side.

Step 5. Bring the ear closer to the shoulder to stretch the neck from the side
Relax your shoulders and tilt your head to the right as far as you can. Use a little hand force to extend the movement and stay like that for about 15 seconds. Then gradually return to normal and repeat on the left side.
You can also hold a light dumbbell (about 2 kg) in one hand while stretching your neck in the opposite direction

Step 6. Do the wing stretch to relax the sides of the neck
Stand up and place both hands behind your back. Tilt your head to the right and, in the meantime, use the hand on that side to pull the other. Stay in this position for 15 to 20 seconds on each side.

Step 7. Use a doorjamb to stretch the levator scapula muscle
The scapula levator is a muscle on the sides of the neck, attached to the shoulders. To stretch it, you can lift your elbow above your shoulder and rest it on a doorframe. Lean against her slightly so that the lower part of your raised arm is stretched upward. Then tilt your head away from that arm. Stay in this position for 15 to 20 seconds on each side.
Part 2 of 3: Doing neck exercises

Step 1. Force your head against resistance in all directions
Place a resistance band or hand against your forehead and use your neck to push against the accessory or palm. Do a set of ten reps, rest, then do one more set. Remember to exert this force to the left, right, and backwards.

Step 2. Lie on your back and bring your chin to your chest
This movement is similar to the abdominal one, but it works the neck. Lie down on the floor and lift your head until your chin almost touches your chest. Stay like this for a second or two and then return to the starting position and finally repeat the exercise 20 times.

Step 3. Lie on your back, lift your head and look to the side
Bring your chin to your chest and turn your head to the left as far as you can. Stay like this for a few seconds and then rotate in the opposite direction for a while longer. Get back to normal and finally repeat the exercise 20 times.

Step 4. Do the dumbbell shrugs
Hold a dumbbell in each hand and relax your arms. Raise your shoulders toward your ears, stay like that for a few seconds, then go back to normal. Repeat the exercise 20 times, rest and do another set. Start with light loads and gradually increase them as you get used to it.

Step 5. Perform the wheel posture to strengthen the neck
Lie on your back on the floor. Bend your knees, support your feet, and place your hands just above your shoulders, with your fingers toward you. Then use your arms, legs and neck to lift your body. Keep your head supported and put as much weight as you can on your neck muscles. Stay like this for five to 20 seconds; then rest and repeat the movement.
When you are more accustomed and stronger, try to take your hands off the floor during exercise and rest your weight only on your neck and legs - unless you have neck problems or injuries

Step 6. Do the dog pose looking down
Stand with your feet shoulder-width apart and lean your body forward until it touches the floor. Use your arms to bend down and rest your head. Stay like this, putting weight on your legs, arms and head for 20 seconds. Then rest and repeat.
- You can make this exercise a little more difficult once you get used to the normal version. To do this, place your hands behind your back and put all your weight on your head and legs.
- If not done correctly, this exercise can cause serious neck injuries. Only do this on a cushioned surface and increase the difficulty very slowly as you get more comfortable.

Step 7. Make the plank when your neck is stronger
The plank is similar to the downward looking dog pose, but you will form a line parallel to the ground with your body - rather than a triangle. To start, support yourself with your forefeet, hands and head; over time, begin placing your hands behind your back to increase the pressure on your neck.
This exercise can cause serious neck injuries. Therefore, consult a doctor before trying to do this and proceed very calmly
Part 3 of 3: Avoiding Injuries During Training

Step 1. Start with lighter loads and fewer reps
In the beginning, even if you are experienced with the physical exercises, don't lift too heavy loads and only do one or two sets of no more than 20 repetitions of each movement. The starting weight will depend on your strength and fitness, but it should be light enough that you can lift the dumbbells and your body without any problems. Only increase the intensity and charge as you get more prepared.

Step 2. Stretch before and after training your neck muscles
It is essential to relax your muscles before and after training to avoid cramps and pain. Don't be in a hurry to stretch.

Step 3. Don't use momentum or momentum to do the reps
You might find that this boost helps with the exercises, but it only gets in the way of progress. The neck muscles are very important and sensitive; so it's best to be careful and stop for a while between each rep.
For example: during the shrug, take your time and stop for a moment between shoulder movements

Step 4. Do the exercises slowly and carefully
You may be used to training, but maybe your neck muscles aren't that strong yet. In order not to suffer sprains or serious spinal injuries, do all the exercises calmly and don't reach an uncomfortable point.

Step 5. Set aside at least two rest days between workouts
Especially when you're starting out, it's best to set aside these two days to rebuild muscle fibers. Even if your workout isn't that heavy, doing too many movements with muscles that aren't used as much can lead to injury.

Step 6. See a doctor if you experience frequent neck pain or stiffness
It is normal to feel a slight discomfort after training, but consult a doctor if you experience severe pain or stiffness in the area worked on - to the point that you cannot move properly. He will give you stretching tips or recommend using a hot or cold compress on the affected area, and advise you to take a break until you get better.