I already had plywood that I cut to size to make each leg and stapled them to make our "K". I bought the smaller package of sheet moss from the fabric store using my 40% off coupon for a total price of $4. I wasn't willing to spend more for the largest roll of moss- figured I could make the smaller package work!
After the wood letter was formed, I cut and pieced the moss on the legs and stapled it on putting the staples on the back of the letter. I used all of my moss with just enough for the letter to be covered on the front and sides.
Staple a ribbon on the back of the letter and hang!
If I find a cheap white satin ribbon, I will probably replace the current one (I already had that one) to give it a little more contrast.