On this super quick video tutorial portrait photographer Nathaniel Dodson (from the website tutvid) demonstrates how to effectively quick mask in Photoshop CC very quickly.
Masks are powerful tools in Photoshop which allows us to accomplish complex tasks with layers in a relatively painless way. On this video Dodson shows a very simple way of adding a mask (although you will probably want to be a bit more accurate when you apply yours).
The idea is indeed very simple – by clicking on the quick mask icon choose selected areas, now paint with the brush (black color), after you are done press Q and now you committed to the section and if you want to place it onto a new layer press cmd/cntrl J and you have your mask on a new layer – super quick and simple.
If you are new to layer masks – here is a very basic intro to the subject by Larry Lourcey