The shoulder press, also known as the overhead press, is one of the best exercises for your upper body. It is one of the most basic movements that define strength - lifting a heavy weight over your head.
This exercise will build you wider and bigger shoulders. And since its a compound movement, it will also work the traps, triceps, serratus and upper chest, and it will even activate your core that needs to work hard so you can do this exercise while standing with a good form.
The shoulder press can be done with dumbbells or a barbell. Using dumbbells require more stabilizing muscles, which results in a greater muscle activation, and it will also help you fix strength imbalances with the dumbbells, because one arm cannot compensate for the other.
Another benefit, is that you can hold the dumbbells in any direction you find comfortable. The barbell forces you to hold your palms straight forward, which might cause elbow and shoulder pain. Rotating your grip will give you a neutral position reducing the stress on your joints.
Don't flare your elbows to the sides. Flaring the elbows to the sides puts you in mechanical disadvantage, and it is unnatural movement for the shoulder joint that might lead to injury. Align your arms in slight angle towards the front.
You can do this exercise sitting down or standing up. Standing will require more work from your core muscles to stabilize your torso. Sitting down will be easier on your core, you can also use back support for even more stability resulting in a bigger isolation of the shoulders. It is also better to sit on a chair with back support if you have lower back problems.
Don't bounce up from the bottom position. Pause for a moment then press the weight up again. Bouncing means you are using momentum for the movement, and it will put unnecessary stress on your joints.
Use the full range of motion. Lower the dumbbells all the way down, and push them up until your arms are fully straight.
Keep your legs straight throughout the exercise. But don't lock them, keep a slight bend in your knees.
Keep your core tight and straight. Avoid arching your back while you push the weight up.