I love the way the examples are shown on this website. Very clear and compelling way to demonstrate the issues that come with colourblindness. A simple heurist

I love the way the examples are shown on this website. Very clear and compelling way to demonstrate the issues that come with colourblindness. A simple heuristic I use is to think about a display in black and white. There should be a way to clearly distinguish or establish contrast between two items (ie. pattern fills in charts)