The three faults are normal, reverse, and strike-slip. In the normal fault the stress is vertical when its at its largest and at its smallest its is horizontal. For the reverse the smallest stress is vertical and the larger stresses are horizontal. And as for the strike slip the the intermediate stress is vertical and the smallest and largest stresses are horizontal.
(what I mean by large, intermediate, and small is least or most comprehensive)
You can write things down, read the material out loud, and read and reread your materials until you pretty much memorize it