Quick Mask (Layer Mask)

1. Make a quick selection with the Lasso Tool .

2. Click the Layer Mask Button. By Holding the ALT key you Invert the Selection.

3. Finish the mask with a hard edge Brush for a clean cut or with a Soft edge Brush for a Featered slection. Make sure you have clicked on the Mask, in Black and White, on the Layers Menu.

Read more about Quick Masks, Layer Masks and Saving Selections