You take the picture while holding the camera above your face...NOT below!
Above - will help you look thinner and it shadows your features better.
Below - will help you look bloated! And it will most definitely enlarge any hint of a double chin...not something any of us want.
After learning this fun new trick I started playing with my camera.
I took this one of me...(And Yes, I took it from above.)
Thanks for the tips Sis!