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select icon you want to use - Apple + C (Copy)

select folder/file you want to change - right click/ctrl click - select get info

click on the small icon - top left

Then Apple-V to paste in the new icon.

thats it!:)
 
http://www.panic.com/candybar/


candybar to change a lot...cost some $$$.


There is also a way to change 1 icon of an app, or 1 file, but if your looking for a system wide change, you should use candybar.

Edit---Beaten by reubs for candybar, and stevehp about the slow, free way.
 
Press :apple: + I on the icon you want to use (i.e. in my case My Pictures).

icon1.png


Select the wee image like I have done in the picture. Then press :apple: + C to copy the icon set (this is more than just a simple image..).

Then press :apple: + I on the new folder/icon you want to change, and do the save as above but instead of copying, you are pasting :)apple: + V).

There is 3rd party icon sets you can download too: http://www.apple.com/downloads/macosx/icons_screensavers/
 
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