When I paste Cmd+V a new layer is created instead of pasting into the layer's mask that I created.
What I'm trying to do is take a black and white layer and make it the mask of a all white layer. This way I have a white cut-out of the shape in the black and white layer.
I'm coming from a background of working with GIMP, which to me is so much more simpler than Photoshop (really, Adobe?), however, GIMP is very slow on OSX so I'm trying to get used to PS.