So I created a triangle template and cut the triangles out from some spring looking scrap material (I cut 2 sides with my pinking shears and one side with regular scissors)

I found some single fold bias tape in a good coordinating color

At the sewing machine, I folded over the bias tape along the raw edge of the triangle

The middle triangle needed something a little extra, so out came the box of felt and jar of buttons

Using a template, I cut a flower shape out of the felt

Hand stitched a button through the center of the felt flower through the middle triangle on the banner

And now the mantle looks a little more like spring!