I would try showing a digital image as well as displaying a sticker on something, like an envelope or a chart etc. My husband made me a very simple light box out of a cardboard box and it has helped my prodcuts look much more professional. I then use PicMonkey, which is a free online photo editing program, to brighten and edit all of my photos. Make sure you use all 5 images if possible. I would also put a little more information into your descriptions.
I would tell the buyer more about your process, materials etc. Also make sure you get your shop policies in place. Be specific about things like shipping, refunds and such.And lastly, just keep adding more items to your shop. Good luck!