I'm sorry I can't speak in english so I use image to tell you the tutorial.
Btw, this is my first Adobe Photoshop tutorial in my blog :)
I use Adobe Photoshop CS5 but I think it also works with the other CS.
This is the tutorial:
Open Adobe Photoshop CS5, File >> New. Width: 100px, Height: 100px, background contents: transparent. Click Brush tool Icon then chage the size into 72px
The brush is done! Then, the next step is open the image that you want to edit.
Oh I forgot to tell you in the image, when you want to use brush tool choose the color with yellow or orange.
I hope you understand with the tutorial :)
Ini dia contoh lainnya.. *loh, pake bahasa indonesia