Go on "File" & then "New".
Click on the brush sign. Then, select your brush.
Paint the sheet all black.
Set the background color to white.
Stamp the white brush a few times.
Press "Ctrl" + "J". This will give you a new
layer.
Click on "Filter" -> "Blur"
-> "Gaussian Blur".
Set it to around 5 pixels.
Pick the brush numbered "300".
Pick a color, paint half of it.
Pick another color, paint the other half.
Look on the right you will see your layer. Right Click (On your layer)
-> "Blending Options".
Set it from Normal to Color.
Press "OK".
