If you've downloaded the .abr file and don't know what to do next, read this tutorial.
- Put the .abr file you've downloaded into the folder /Users/{username}/Library/Application Support/Adobe/Adobe Photoshop CS3/Presets/Brushes (on mac OS X) or C:\Program Files\Adobe\Photoshop\Presets\Brushes (on Windows) .
- Then open your Adobe Photoshop, active brush tool, go to option palette and click on to open the brush preset picker.
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Then click on little triangel in the right upper corner.
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Next on the list you choose 'Load Brushes'
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In the dialog box choose the .abr file you want to load and your
new brushes appear in the Brush palette and are just ready to use.