Focus on the eyes. Did you ever take a snapshot that you thought would be perfect and when you got it back it was just a little fuzzy and out of focus? Low light situations during the holidays make this a particularly likely situation. When taking a picture of someone try to focus on the inside corner of their eye. The distinction between the skin and white of the eye helps the camera to focus and if the low light is causing a shallow depth of field, the most important parts of your picture will still be clearly in focus.