Come into a high plank position. Turn the inside of your elbows forward.
Imagine that your tailbone wants to touch your heels. This will help activate your lower belly and protect your lower back.
Shift your weight forward so that your shoulders go past your wrists.
Gaze down and keep your neck long reaching forward while imagining your feet pulling back. This helps keep some of the weight on your feet.
Slowly bend your elbows and squeeze them into your body, sliding your shoulder blades down your back. Shoulders away from your ears.
Bring your shoulders in line with your elbows.
Modify the posture going down on your knees and using blocks. Start with the highest side of the blocks. Try to work at engaging your core and squeezing your elbows.
Use the middle size of the blocks.