Stephanie, here are some great tutorials on using ribbon on the tree. Have fun with it!
I put mine on from top to bottom, some like to wrap it around the tree. I attach them at the top under the tree topper (mine is an angel) and run them down the outside of the tree. Hubby has a big Norfolk Island Pine in the bedroom and he purchase mini ornaments, LED mini bulbs and a tree topper that had the ribbons attached to it. It looks really nice that way in the bedroom.
Loop it around starting from the top or from the bottom and adjust as you go.
You could just string it along, draping it off the branches so it swags. Or you could create a ribbon chain and then drape it. Here is a post I wrote that shows a unique Christmas tree stand. Towards the end of the post, you'll see a vintage ribbon chain I made and draped exactly that way!
I Like wired ribbon. I use the "wind around" method but I like to weave it inside the tree as well as outside. Be sure to put it on the tree before glass decorations. Have fun!!