Quantity   Component name
1 × PBT keycap this is important -- ABS will melt in the oven | https://www.amazon.com/gp/product/B06XJSW4BF/
1 × polymer clay in various colors this is what I bought -- https://www.amazon.com/gp/product/B07F68L2DW/
1 × oven 255F for 18 minutes seems to work
1 × satin polyurethane this makes the keycap a little bit shiny