There are small variations in the way yogis do this sequence, but the most important thing is the synchronization of the motion of your breath with the movement of your body. Basically, all upward movements are coupled with inhalation, and downward movements with exhalation.
Swan dive into a standing forward bend, exhaling through your nose and placing your hands on your legs as close to your feet as you can. Bend your knees a little if your hamstrings are tight, to protect your back.
Exhale and step, or lightly hop, your feet behind you to get into a Plank pose, arms straight underneath your shoulders and legs straight behind you. Your back should be flat and your core engaged. Hold for a second, then, in a snake-like movement, lower yourself towards the floor. Then lower your chest and chin to the floor, keeping your elbows close to the sides of your ribcage, and flatten your feet to the floor.
Inhale as you push down with your arms and raise your head, shoulders and upper body as far as you can without straining. This is the Cobra pose. Look upwards, roll shoulders back and down and keep elbows in. Firm up your kneecaps and thighs to prevent them lifting off the mat.
Exhale into Downward Facing Dog; walk hands forward and slightly farther apart than shoulder width, and spread fingers wide for stability. Then curl toes under and press your hips upwards so your body is in the shape of a triangle, with your bottom as the apex. Make sure your neck and shoulders are released and relaxed. If your hamstrings are tight, keep your knees slightly bent. Take five deep breaths.
Lower arms into original standing pose.