I would highly recommend you to download and read this tutorials. They are nice and easy:
Yep! Here they are
But you may also read how to download or install brushes here)
How do I download the brushes?Usually you should just left-click on the “Download” button in the left of a deviation. If it does not work, try to disable any download managers and then right-click and “save as…”. If dA tells you about errors, try it later.
How do I installloadopen brushes into Photoshop?First of all find a file you have just downloaded
Unzip it if necessary. You need just a .abr file. Start PS. Select Brush tool. Open a window where you can select different brushes, click on a little triangle and select “load brushes”. Find you .abr file and double-click on it. PS will ask you, should it ADD this brushes to previous loaded (append button) or remove all loaded (not from your computer – you can load them back at any time) and show only this new set. Or even cancel 
If you have a slow computer, I’d recommend to select replace.How do I set up sizecoloretc for brushes in PS?Yey, a big question ya know. Try to read photoshop guide itself. Or try this candy again
How do I use PS brush set in other program? Photoshop Elements Simply:
Close PS elements if it's running. Place the *.abr files into:
Program FilesAdobePhotoshop Elements XPresetsBrushes where X is the version number for your version of Photoshop Elements.
Other software?
Well, now we have some more problems. After opening this account I learned about so many new graphics software BUT I don’t use them myself. I’m in love with PS
.Damn well.
Usually you’ll have to work with png images, and then load them to a program you use and convert them to a brush. I, and many artists provide psd or png packs for their brushers.
If you program doesn’t work with psd (O_o) or there is no anything just abr file,
try this link - abr file -> png file -> any program
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I will add some more useful links later. Any suggestions are welcome
