I used a large round wreath base. And started by wrapping it in yarn (I just used some cheep stuff, Vanna's Choice maybe)
This step is not necessary but I thought at first I wouldn't put as many hearts on so it would be nice to have a little something extra on the base. Wrapped some red and white Christmas ribbon around the wreath.
Next I cut about two dozen hearts out of red, white, light and dark pink felt. Again cheep craft felt, though I think it would be that much better in a wool blend, however my fabric store doesn't carry wool felt in any colors that I like.