Summary Make your own keychain! Use any image - selfie, loved one, fav band. Upload any image and make your one-of-a-kind key chain. To help you print in different colors I improved my plastic opacity test print. See instructions for more details. I included an improved version of my opacity test STL file so you can find the best number for the layers setting based on the color of plastic you will be using. NOTE- I have some detailed image prep notes in my instructable here: http://www.instructables.com/id/Custom-Glowing-3D-Printed-Ornaments/ Instructions Open in customizer, upload image, change any settings you want, download and print. Don't maker the border too thin. I left some PLA key chains in a parked car and the heat of the sun made a 1.2mm thin key chain warp.(see pictures) If you are not sure how many layers to use with a certain color then NO WORRIES! I made an improved version of my opacity test strip for you! It's smaller and prints faster. lithopane-test_opacity_3mm.4x4-pad1.3.stl For the opacity test print slice at 0.1mm layer height, 100%fill, initial layer 0.1mm. Each row is a 0 - 10 layer opacity scale. Hold it up to the light to see at which thickness the light stops passing through. I made it go all the way to 3mm thick since some of the transparent plastic colors would be able to go that far. NOTES: For dark colored plastics make sure you keep the boarder thickness 3mm or more since these thin prints can warp in a hot car. (see pictures) If you are using words in your image, make sure to reverse the image before uploading so the letters are not backwards. NOTE- I have some detailed image prep notes in my instructable here: http://www.instructables.com/id/Custom-Glowing-3D-Printed-Ornaments/