Use brush on old fashioned, real white paper to make some more or less straight lines. Scan them in gray or B&W mode on 300 pix/inch resolution.

You should get an image that looks like this:

How to create your own custom brush in PhotoShop

Now you can simply create brush in 2 steps.

Use Rectangle Marquee tool to make selection. Go to Edit - Define Brush Preset.

How to create your own custom brush in PhotoShop

New Brush dialog pops out, rename it if you want.

How to create your own custom brush in PhotoShop
Your new brush in Brush Palette is now available for selection.And, if you need these brushes but don’t feel like going through all this, get them for free

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