The next thing I'm going to do is crop this extra white
space out from around the image. One method for doing this is to select
the "crop" tool in
the toolbar, select an area with the mouse, and click "crop" on
the pop-up, which crops the image to the selected area:

If you want to remove a large amount of a single color around the
edges, you can also crop the image by going to the "Image" menu
and choosing "Transform," and then "Autocrop." In
this example, I've used autocrop to remove the solid white area around
this image:
Choosing "Autocrop":

The autocropped image:
