Q&A for How to Paint with Coffee

Since coffee is so watery, I think watercolor paper is the best choice. I would test the spray preservative first to make sure it doesn't react weird.

Any will be okay, as you are not trying to brew coffee, just wet it. It would be best to use a medium temperature because with hot water, you may burn your hand and it may be harder to dissolve in cold water.

Yes, as long as it has the deep brown color. Espresso is more expensive, but use whatever you like.

Black coffee is best for coffee painting because you can dilute it for lighter shades or use it concentrated for darker values. If the dried color isn't dark enough, you can apply another layer once it's completely dry. Avoid doing this on wet canvas or paper to prevent bleeding. The techniques are similar to watercolor painting.