Download the latest version of FINDER on the bar to the right at the top of the page.
There are two versions: FINDER and FINDERstandard.
FINDERstandard uses the standard icon names that come with the iPhone and third party applications.
FINDER uses custom icon names. To edit icon names, a plist file in Springboard.app must be amended. This is not recommended for those unfamiliar with coding.
Choose the appropriate version and download. Unzip the FINDER folder and place it in ~/Library/SummerBoard/Themes.