Sit down on a shoulder press bench or an adjustable bench set up in the shoulder press position. Put each dumbell resting on your thighs above your knees. Then raise them up to shoulder position with your hands facing away from you. Inhale.
Press each dumbell up directly over your body until your arms are almost at the top, but never so that your elbows fully lock out. Pause, squeeze your shoulder muscles and exhale. Then lower each dumbell until your upper arms are about parallel to the ground. Inhale. Repeat for reps.