Well, first you'll need some lights! The brighter the better! Then, just wrap them around the tree, starting from the bottom and working your way up. Be careful not to wrap the wires too tightly or you might damage them. Once you've covered the tree with lights, plug them in and voila! You've got a festive, illuminated Christmas tree. Don't forget to put up some decorations too, like ornaments or a star on top!