Also, a little note here. If you are doing small chunks of colors similar to the Mizzou wreaths below, I would leave a little yarn hanging from the knot and use it to secure a knot to when you are ready to switch colors. I laid it flat under the yarn I wrapped so it wouldn't be seen. That makes it a little easier to tie it off at the end. If you decide to use one color, I let it hang until I was done and then tied it off where I started.
There isn't much more to it than that. Just tie and wrap, switch colors if you want. Then decorate!
Finally, I glued the flower to the felt and pinned it down through the Styrofoam.