Ah, it's that time of year again, when the holiday season is upon us and you're wondering how to put outdoor Christmas lights on a tree. It's a common question, but it can be a bit tricky, especially if you've never done it before. But don't worry, I'm here to help you out! The first thing you'll need to do is to find a suitable tree. Look for a sturdy, stable tree that can support the weight of the lights and decorations.