Here is how I made these...
For some of them I used yarn. I carefully laid out my shape and needle felted the yarn into the felt square by slowly following the yarn to mke a heart shape.
Once the outline of the heart was finished I filled it in with more yarn. I them "sandwiched" a piece of batting between two felt squares and blanket stitched the edges in a colored thread to match the heart!
I also cut out heart or butterfly shapes from fabric. You can use preprinted fabric that has hearts or butterflies on it or just cut the hearts out of any fabric like making construction paper hearts when we were kids! I slowley punched the heart onto the felt backing. I tacked it in a few places first so it would keep its shape.