[U-Boot] how to create patches for mailing

Hi!

I want to add a new board support to u-boot. So I did the following:

1) git clone git://git.denx.de/u-boot.git u-boot-dev 2) modified existing files, added new 3) built the tree for my board, beagle and overo - OK 4) git format-patch - nothing happens

are there any step by step instructions how to create and submit patches to u-boot mail-list? Reading this http://www.denx.de/wiki/view/U-Boot/Patchesdoes not give sufficient comprehension how to do it..

I appreciate any comments..