Finally you can send your commit to the development mailing list and to the patchwork server.

If it is only a single commit (one patch) you can do a:

git send-email -1

which will send your last commit to the patchwork server and development mailing list.

Sending multiple related patches (patch-set)

Add the option --in-reply-to <mail Message-ID of first mail> to submit your last commit as a reply to a previous mail (essentially creating a mail thread). This way you can add multiple related commits to patchwork as a single "patch-set"

Another method is to save your commits in patch files and then sending them to patchwork in bulk:

git format-patch -o /home/joe/src/ipfire_sandbox/my_patches next

Git will now export each commit in the current branch since next as a seperate .patch-file under /home/joe/src/ipfire_sandbox/my_patches where you can review them a last time before sending them to patchwork.

To finally send all exported patch-files to patchworks/the mailing list in one go as a patch-set:

git send-email /home/joe/src/ipfire_sandbox/my_patches/

(this method also works if you only have one commit)

Adding an introductory mail

Generally it is a good idea to add an introductory mail and/or patch-set summary, explaining to the reviewers what the patch-set is about, why the patch-set is needed and/or what it does. This will help the acceptance process of your patch.
Do this by adding the option --compose which will cause git to invoke a text editor in which you can edit your introductory message. Start the mail-subject with [PATCH 0/x] replacing x with the number of patches, to make clear that this is an introductory mail for a patch-set.
Git will then send your introductory mail and add your patches as replies to that mail, creating a mail-thread.

Send a new revision of a patch to patchwork

In many cases your submitted patch or patch-set will be discussed with you in the mailing list. This discussion may result in the need to update the patch. Submitting an updated patch or patch-set is exactly the same as described above except that you add a parameter -v followed by the revision number during the export of your commits to patch-files:

git format-patch -v2 -o /home/joe/src/ipfire_sandbox/my_patches next

This will add [PATCH v2 x/x] to the Subject(s) of your mails, indicating the second revision of your patch(-set). Review the patch-files and send the patches to patchwork as described above using the send-email Git command. Also here you add the option --in-reply-to <mail Message-ID of first mail> if you want the patch(-set) to be a reply to another mail on the mailinglist.

Also again, add --compose if you want to add a summary of what was changed in this patch(-set)-revision versus the previous submission.