This an AMRAP, "As Many Rounds As Possible". You are free to take breaks whenever you want, even in the middle of an exercise. The idea is to go through this entire set of exercises as many times as you can during the set amount of time you give yourself (15 or 20 minutes). If the timer goes off and you are in the middle of a round, feel free to either finish off the round or just stop the workout if you are pressed for time.
Some music if you need:
Start in downward dog, keeping your core tight and your arms and legs as straight as possible. Bend your elbows and as you begin your descent down, begin to drop your hips and straighten your body out. At the bottom, you should be in a plank-like position, with your elbows bent. Push up, acting like you are doing a cobra pose, but do not let your body touch the ground (just your hands and feet). Then reverse direction. Try to make this a smooth as possible. That is one rep.
Start in standing position. Take your right leg and cross it behind your left leg. Be mindful of your center of gravity. Inhale as you lower yourself. Make sure the front knee stays stacked (above) your ankle. Exhale and raise yourself back up, feel the weight of your body distributed between the ball of your back foot and the heel of your front foot. As you return to standing position, do a normal squat. Inhaling on the way down. On your way back up, exhale and keep the weight on your heels; flex your glutes and your quads. Repeat other side.
Lie face down. Raise your forehead slightly off the ground a few inches and extend your arms out in front. Raise your left hand, your right leg, and your head simultaneously. At the top, pause for 1 second. Release and go back to starting position. Repeat other side.
Lie face up with your arms and legs extended and resting on the floor. Keep your abs tight and exhale while lifting your hands and feet to meet over your torso, rolling your core as you sit up. Inhale and lower your arms and legs back to the floor. Repeat.