This tutorial is based on the PNG files on this site, similarly works for other PNG etc files. Chevron pattern files ?
Open the PNG file or use the place command in Photoshop - that is the first thing, once loaded it can then be manipulated in a number of ways such as adding effects or using it on channels etc - as with most things in PS, there are 100s of ways of creating new and exciting brushes
Tutorial by: Andrew Buckle
Works with: Photoshop CC and CS and standalone, Elements
Other tutorials: Tutorial links
Videos: Video tutorials
Open PNG file and go to the edit menu define brush. You can define the entire file or just use the rectangular marquee and then select part of the artwork and define that. Once you have a brush defined, you can also go to a new document and then apply that multiple times, perhaps mixed with effects etc, and define that as a new stroke as well
You can also open the PNG file and then define it as a pattern via the edit menu and then go to the layer menu and new fill content and add as a new layer which can then be flattened by the layer menu and edit define brush command. You can select the entire layer or perhaps part of the layer. You can also combine that with effects and then define that as a new stroke as well.