1. Download Mondrianum and install it. (copy the folder to Applications > Photoshop > Plugins)

2. In Photoshop, go to the Preferences > General. (Command + K)

The very first option in this pane is the color picker dropdown menu. Select “Apple” then close preferences. (click OK)

3. Double click on your foreground color to bring up the color picker, and you should now see the Apple color picker instead of the Adobe picker we’re all used to.

Click on the icon at the top on the far right to bring up the Mondrianum panel.

Now to use the panel you can simply click on the swatches at the bottom, or you can export an entire set of swatches to import to any Adobe app. To do this, click on the little arrow to the right of the color combo you like, and choose “Download as Adobe Swatch Exchange file.”

Now the export/download dialogue appears. Just click “Save File” and it will be saved in the same folder that your browser download files to.

To install, find your swatch file in your downloads folder, and move it to the adobe app you want to use it in > Presets > Swatches folder. Done! now you can load the swatches from the swatches panel in your Adobe app.