Think of pictures of yourself. There are ones you like, and ones you'd like to burn or at least drag to the trash can on the computer screen. Maybe it's because the camera wasn't capturing your "good" side. Science tells us that most folks like looking at the left side of faces...this article in Time magazine says we humans find that side of the face "more pleasing." Go figure. Granted that doesn't mean the left side of your face is your good side.
How do you find out which side is your good side? There's no real magic -- it is all about looking at pictures and the mirror. Look through old pics and find ones you really like of yourself. Take note of where the camera is in relation to your face, how your whole body angled, all of that.
Play around in the mirror with angles, with light, tipping your chin up or down. I mean, just think about all of those celebs that don't seem to take a bad picture...it is because they always stand and tilt their head the way to maximize their look. Why shouldn't you do that the next time you're posing for that family photo?
Do you know your good side? Do you often pose in the same way for pictures?