For Wade's Monthly Photos, I made my own Month Decals to apply to Wade's onsie. Instead of sewing the decals onto the onsie, I made an illusion decal by stitching around my fabric decals and then attaching them to the onsie using a safe adhesive. This way, I can reuse the decals if I want to in the future (or sew them into a quilt eventually).
You will need fabric markers, fabric pieces--I used Moda Honeycombs in color patterns and a basic white print, contrasting thread and then pinking shears. I stenciled numbers using fabric markers on the basic white honeycomb piece and then traced it onto the color piece. I sewed the color piece and a white piece together for extra support and stitched around with the contrasting thread on a 1/2" seam. Then I went around the finished honeycomb with pinking shears to give the perimeter of the decal a little flare.