The process is virtually the same platform wide. When you download the file SOMETIMES it is archived in .zip or . rar or something. Regardless you you need unpack it. The brush files should be ".abr" format. Navigate to your program folder and then to adobe and find the brushes folder. (The default should be similar to this path: "C:\Program Files\Adobe\Adobe Photoshop CS2\Presets\Brushes") Unpack those files/file into that folder. Then run Photoshop, create new, then with the brush tool selected, right-click anywhere on the canvas and a context menu will appear. There is be a small button with an arrow pointing to the right in that menu. Click that and the name of your newly installed brush pack should be in the side menu that appears. Just select it and click "ok" and the brush options will change to that specific pack. I hope this helps. :)