Most of the free Photoshop content on this site is distributed as Zip files to reduce download time. Before the files can be used, they must first be extracted. Zip file extraction is built into the operating system in Macintosh OS X and Windows XP. Consult your computer help if you're not sure how to extract zip files. For earlier operating system versions, you will need an unzipping tool such as Winzip (Win), Stuffit Expander (Mac), or ZipGenius (Win) to extract the files. After extracting the files, place them in the appropriate folder as indicated above.
Note: Most of these files can actually be saved anywhere on your computer, but to make them available from each tool's menu, they should be located in the appropriate folder under Presets. If you keep the files in another location, you will need to navigate to that location each time you want to use them.