how to put christmas lights on a tree outside

(Thoughtfully) Well, that's a tricky one. I suppose it depends on the tree and how you want the lights to look. If the tree is tall, you might want to use a ladder to reach the top branches. If the tree is smaller, you can probably use your hands. You'll also need to make sure you have enough lights to cover the entire tree, and that they're the right kind of lights for outdoor use.