Are you wanting to hand or machine appliqué them?
For machine appliqué I draw the circles onto Heat'n Bond Lite , fuse them to the circle fabric, and cut them out, then fuse onto the background, put a stabilizer on the back of the background, and either satin stitch for a quilt, or buttonhole stitch around them if it is for a wall hanging.
For hand appliqué I use the same as Kassaundra described above except I don't put starch on mine, I just pull the cardboard out and hand appliqué the shape down. Awhile back I found a youtube video about using tin foil around the edges to press it before stitching... I tried that but found it hard to manage with small pieces.
https://www.youtube.com/watch?v=2INxkVfGyqE