[Gimp-user] irregular cropping

["Ward Ricker" <wadori comcast net>]

I downloaded GIMP in order to crop around an odd shaped picture, i.e.,
remove the white background around an object in a rectangular picture so as
to leave an odd-shaped image.  I have not studied how to use GIMP.  Since
this is the only thing I wish to use it for I am simply following the
third-party instructions from the website where I found out about it, but
they are simple.   I am:

                Opening my image in GIMP

                Using the Free Select Tool to go around a click on all the
corners, thereby outlining the portion of the image I want.

                Going to Select - Invert in order to deselect the part I
want to keep and select everything else.

                Hit Delete.

When I do so I am expecting everything outside of the desired picture (i.e.
the white area) to go away as the third-part tutorial shows.  Instead,
everything gets deleted.

 

I also tried selecting portions of the white area using the Free Select Tool
and not doing Select - Invert.  Similarly, it deletes my entire picture
rather than the selected portion when I hit Delete.  Can you tell me what is
going on here and why it won't delete only the part that I wish to delete?