This is a funny name for a very challenging exercise! The key points to remember when doing the exercise are the following:
Dead Bug is one of the more under estimated and under utilized exercises for core strengthening. I am demonstrating two different ways to do this exercise.
The first is getting the basics down of: - Bracing your back by finding your pelvic bones and tilting your pelvis in towards your navel. This protects your back and prevents feeling lower back pain during the exercise. - Bring your knees with legs bent over your hips and hip width apart - Slowly begin to extend one leg straight and down towards the ground without touching the floor, bring the leg back up and repeat on the other side.
PROGRESSION - Begin as you did in the first option but this time bring your opposite arm parallel to your ear. Return to the starting point and repeat on the other side.
I would recommend 10-20 reps until you feel you can comfortably progress to more.