Very simple, in fact, I usually just mix it up in my hand. Just take some of the wood dust, mix it with either thick gluewash, or water and wood glue. Gluewash = diluted wood glue, kinda like the shit they gave you in kindergarten for gluing construction paper. Anyway, mix it up and keep adding gluewash until it's a thick paste. It should be creamy and have strong peaks. It should also have a yellow tint to it. Otherwise, you need more glue. Honestly, it's very easy to figure out once you start it.