Okay, this is a tutorial for the ribbon trees I made last year. Unfortunately I don't have pictures of the process, BUT, it's very simple to follow.
Supplies:
Ribbon (about 6 types — approx. 4 yard roll of each is fine for a 12" cone / tree… it's really up to you as to how many types you want on your tree…)
Pins (decorative "ball" pins from the sewing aisle)
Foam cone (in florist aisle at Michael's or Jo-Ann, whatever size you'd like)
Decorative topper/ Floral pick (you can also find these at Jo-Ann / Michael's… or use whatever you like, even a small ornament would work nicely…)
Step 1: Cut some of your ribbon into approx. 4" strips. I don't cut ALL my ribbon, I just cut it as I go… this way I don't waste any. (Of course truth be told, I made so many of these that I ended up making multiple repeat trips to the store for more ribbon… I think I purchased about a quarter of their total stock!!)
Step 2: Fold the ribbon in half, decorative side out. Take one of your decorative pins and pin it to the cone, near the base. To do this, look at your loop…. at the top where the two ends meet (not the loop end) is where your pin will actually go in. You want to put it about 1/4" to 1/2" down from the top, so as you're layering, the pins will show (very pretty if you use the decorative ball / pearl pins, because they look like mini ornaments.) Angle the pin down when you stick it in. (This way, as you get nearer to the top, you don't have any pins poking out the other side of the cone.)
NOTE: For your first row at the base, I would pin it leaving about 1/2" (or so) of the loop hanging off the bottom… not too much but not too little. You don't want any of the cone showing. This way the ribbon can actually "fan out" on the bottom, which is pretty if you don't use anything else as a base.
Step 3: Repeat Step 2, pinning right next to the ribbon you just pinned. You actually want the edges to overlap a little so the cone doesn't peek through. Repeat all the way around the base, then add additional rows all the way up the cone. (Basically it's just rows of loops.)
Step 4: When you get to the top, cut a piece of ribbon to wrap around the very top… just to cover up any edges showing. Then add your topper…. I like to hunt for neat wire floral toppers or "picks" I think they are called…
If you'd like to place this in a base of some sort, stick a bamboo skewer up the inside of the cone. Place an appropriate sized block of florist foam into your base and cover with spanish moss. Then stick the skewer in the block.
So simple… and this makes a beautiful gift as well, for a hostess, teacher… anyone really. You can attach your own lightweight "ornaments" if you'd like, or even attach small bows in spots with your decorative pins. The cones come in all sizes as well, so you can make miniature or large trees.

You can see more trees at my Flickr.
Happy Ribboning!
