Not only do Christmas decorations transform a home, both inside and out, they can make for fantastic photographs.
1) Whatever you're shooting – baubles, tinsel, table decorations, the tree, pine cones, mince pies, piles of presents, Christmas cards, outdoor lights or even the inevitable potted poinsettia – you need to minimise blur, so choose a high enough ISO and a wide enough aperture to let you hand-hold without risk of camera shake, or use a tripod to shoot at slower shutter speeds, firing the shutter either via your camera's self-timer or a remote release. You'll also need to check the white balance as indoor lights can give your shots a warm cast. You might be better selecting tungsten or one of the other white-balance presets; alternatively, if you shoot in NEF (RAW) you can sort out casts on the computer afterwards, although it's always better to strive for the best possible result in-camera.