I sewed it down to the white background piece, and then began the rest of the logo. This atom symbol consists of three overlapping ovals. I eye-balled the ovals themselves, but used a ruler to get the points spaced correctly.
I then cut this shape down to the correct size and pinned it directly to the rest of the logo to use as a sewing guide. I did this because I didn't want to draw on the fabric, even with tailor's chalk, for fear of it staining the white. It worked out pretty well, and once the first lines were down I just ripped off the paper. I then went over the lines again to make them bolder and to straighten out anywhere that the lines looked wobbly.
So here you have it, Atom Eve's chest logo made from appliqued fabric and top-stitching!