You can't really control the lighting or background in pictures, but you can to an extent control other things. It's generally accepted that the color blue looks best on people in pictures or on TV, so wearing that color for your special occasions can make you look optimal. I'm assuming shades of blue, and colors similar to it, such as green or purple have the same effect. Is that to say that colors such as yellow or red don't look good in pictures? Not necessarily, but they're definitely harder to pull off. It really depends on skin tone, and wearing any color that's too close to your skin can have a negative impact on your overall look for a picture.

The angle of your face is also very important. Should you turn your head a little? Tilt your chin in a certain direction? Look straight at the camera? Above all, only the person taking the actual picture can tell you this for each of the pictures. If they have the patience, they can tell you what looks best, granted they have some sort of an aesthetic sense. For Facebook photos though, you shouldn't really worry about this too much. The most you can do is "study" how you look in all of your pictures, and what angles you were facing and such. See what looks the best, and apply it in future photos.

Hopefully now you've learned a thing or two about how to look photogenic in photos for men, and for women.