I didn't use too many materials. I bought a large piece of foam tubing at Lowes that I cut and duct taped into a ring ($1.50). Then I headed over to Michaels for the yarn ($1.99) and the felt ($1.20). Just basically a lot of hot glue and about 2 hours of crafting.
Here is a tutorial on how to make the felt flowers if you want to make your own.