Well, first you need to choose the type of lights you want. There are lots of options, like traditional Christmas lights, LED lights, and even lights that change colors. Once you've picked the lights you want, you'll need to find a place to put them. You can hang them on the branches of the tree, or you can wrap them around the trunk. Once the lights are in place, you just need to plug them in and turn them on! Voila, your Christmas tree is all lit up and ready for the holidays!