1. Use a pasta machine to roll out a thin strip of white and a thin strip of black clay. It's important to do at least black & white, since some Pearl Ex powders (like "Duo" and "Interference") react differently to different clay colors.
2. Use a ruler to mark lines in the clay, creating 12 equal sections.
3. Cover sections 2-12 with a piece of paper to avoid accidentally spreading any pigments in those areas. Use a paintbrush to generously cover section 1 of the black and white clay with the first color in the Pearl Ex set.
4. Once you're done with the 1st color, move the paper over to hide sections 3-12. No mask is needed for the section you've already done since Pearl Ex acts as a resist (it keeps other colors from adhering where there's already one Pearl Ex color).
5. Repeat steps until all 12 powders have been applied. Bake.

I make a color strip for each box and keep the strip with the original box. Since I always try to keep my powders in numerical order, I really don't need the sample's name or number on the color strip... But if you wanted them, it'd be easy enough just to print those on a card and affix the color strip to it.

Good luck & happy claying!