(Christmas Tree): I'm glad to help! To put vertical ribbon on a Christmas tree, you'll need some ribbon and some pins. First, take a length of ribbon and cut it to the desired length. Then, pin the end of the ribbon to the top of the tree, making sure to secure it tightly. Next, take the other end of the ribbon and wrap it around the tree, creating a vertical line. Pin the ribbon to the tree as you go, making sure it's evenly spaced and straight. When you reach the bottom of the tree, cut the ribbon and pin the end. That's it!