How to submit a patch?

[Willem Rein Oudshoorn]

I was playing with images in emacs and discovered that the 
:foreground and :background properties for the image type XBM do not
work on the Cocoa version of emacs.

I have changed image.c nsimage.m and nsterm.h so it now
honors the attributes.

So how do I go about getting this incorperated in emacs?
I have used bzr to get the source, so what is the next step?

Also note that I did sign FSF copyright papers years and years ago,
but that was for the GNUstep project.  I am not sure if that is also
applicable to emacs.

Kind regards,
Wim Oudshoorn.