Do you also have lots of fabric left over of your sewing projects ? Dig in your boxes or baskets, pick out the ones with the brightest colours. Also find some colourful yarn, ribbons and shiny buttons. With paint and stamps you can make the cutest decorations.
I used a cake doily in the middle, put a bit of paint on a brush and tap on the doily. Once removed you'll see a nice “plate”.
Cut fabrics in shape of a spoon, knife or fork and stitch them on a rectangular piece of material with for instance knitting yarn or embroidering thread.
Use buttons and ribbons for decoratation. If your making placemats with young children you can use glue instead of sewing the ribbons and fabrics.