Using a Barbell 

With a comfortable working weight

Safely step over the barbell, and grab the bar slightly shoulder width apart 

Removing from the rack find a stable position and your proper posture

Slowly raise the shoulders/trapezoids toward the ears without any rotation

While coming upward, raises the barbell above your glutes squeezing your trapezoids

Once you reached your highest tension point, slowly come down to your starting position

After a complete repetition, repeat steps