It depends a lot on the type of camera you use, but if you're unfortunate like me and only have a cheap digital camera with a flash that's WAY too bright... here are some tips for getting decent photos:
- Always use flash, but filter it with toilet tissue or paper towels. Usually, with mine, I fold over a piece of paper towel once or twice and it filters the brightness of the flash a bit. Either hold it against the flash (with your fingers out of the way of it) or tape it on there if need be.
- Make sure the focus is going in the right spot. With my camera, you have to hold the button halfway down and listen to the little mechanical sounds to make sure it's focusing in on the proper location.
- It helps to be able to predict their movements a bit. That way you know right when you should hit the button at a point where they stop moving for a second.
- If photographing through glass, take the picture at an angle so the flash doesn't reflect on the glass in a spot that covers up the bug.
- Make sure the "flower" (macro) setting is on!