Ok I have GIMP 2.0 and I wanted to use it to color line work.

Specifically, I wanted to do the thing where you can just cover an area with paint, even going outside the lines, then you shade in the parts you want and remove the paint that is outside the lines. In the live Penny Arcade drawings I've seen him do that as well.

Basically this link is the sort of thing I want to be able to do (not the anime, shut it.)

Problem is little chick just goes by at lightning speed and no matter how many times I watch it I can't figure out what the hell she is doing. Especially in regards to layers (like, which layer am I on? Even when I select "go to bottom layer" or whatever I can't see the name at the top of the window change or anything so how do I know?)

Also when she removes the colors, what the fuck is she doing? I see her draw lines around something super fast (Do you draw the lasso around the chunk of color and go super close to the lines or do you select the whole area you painted in?) and then she says she hits "clear" (Doesn't say where she hits it, I've only found a "clear" button under "edit") but when I do this it either does nothing or takes a chunk of the picture away (I'm assuming this means I'm on the wrong layer but once again, how do I know which one I'm on?) She also says something about removing by color but whatever she clicks on I can't freaking see what she does.

tl;dr Please to be sharing GIMP knowledge. Specifically how to color stuff.