Although not recommended, if you wish you can submit your changes as patches.
You will need to have a local git repository and have your changes saved as git commits in a dedicated development branch.
For details, see the git reference manual.
You will need to first make sure that your branch is fully up to date (Section 13.4.2 on page ).
The patches are then created by typing
$ git format-patch master
This will create one *.patch file per branch commit. These files can then be emailed to the nmr-relax-devel at lists.sourceforge.net mailing list (this requires a subscription).