DPM patterns tutorials?

Hey, I’ve been looking for a while for a DPM tutorial on google n’ stuff, but I can’t seem get a straight answer on how to make one (and I know you can, I’ve seen DPM textures on FPSbanana, but no one there wants to help, it seems).
So, any idea, knowledge, obscure tutorial that might help me?

Thanks in advance (and sorry if this is in the wrong section).

Founded in 2004, Leakfree.org became one of the first online communities dedicated to Valve’s Source engine development. It is more famously known for the formation of Black Mesa: Source under the 'Leakfree Modification Team' handle in September 2004.