Adjust the seat so that your push will start at chest height. Adjust the handles to let them pick up the weight slightly behind your chest but not too far
Set the planned weight. Sit down and lean back against the back support. Grab the handles from the outside. The palms of the hands face each other. Pull the chest up. Activate the core. Pull the shoulders back and down. Press the hands forward against the handles to feel the weight on the arms. Engage the muscles in the back of your arms and the chest
Extend the arms. Push the hands forward away from the body. Keep pulling the shoulder blades back in the same time
Extend the arms until they are straight but not locked out. Keep pulling the shoulder blades back and down. At the same time pull the arms towards each other with the chest. Hold this position for a moment
Bend the arms again. Bring the hands back towards the chest. Keep the elbows low, shoulder blades pulled back and down.
From the start position repeat for the planned number of times
Build a strong chest. Strength for horizontal pushes. Strengthen the chest, arms, and shoulders, especially m. pectoralis, m. triceps and m. deltoidus anterior