git remote add my-subtree firstname.lastname@example.org:your_username/your_repo.git.
git subtree add --prefix=the_folder/ my-subtree master --squash.
git subtree addand then the name of the folder it will live in and finally the repo name and branch. The
--squashoption avoids storing the full history of the subtree in the parent repo, including it as a single commit.
the_folderand commit. Your parent repo, along with the files in the subtree, will be updated. But the subtree will not.
git subtree push --prefix=the_folder my-subtree master. And the same command but with
pullto pull any new changes.
Edit on Github!