Use your free hand to hold on to something to stabilize yourself (a pole, top of the back support of a seat, some piece of sturdy gym equipment). If you’re doing the exercise seated, you can place your hand on your opposite thigh or hold onto the bottom of the seat.
With the dumbbell by your side and a slight bend in your elbow, raise the dumbbell out by your side until it gets to shoulder level.
Very slightly tilt your pinky finger upwards as you raise the dumbbells outwards. This should help you feel the exercise better on the side of your shoulders.
Then slowly lower the dumbbell back down to your side. Repeat this for however many repetitions you’re aiming for, then switch arms.