There are several ways of tagging a new version for your release. One of these is using Github. The drawback of using Github for this, is that it will also create a release complete with a Zip and Tar.gz package. Something we don't want to promote too much when we favor packagist for keeping packages up to date.
This tutorial will explain how to tag versions using git, the command line tool. I assume you have some basic knowledge using Git, with pushing and pulling and merging code.
Getting existing tags
git fetch --tags
Creating a tag
git tag 0.1.0
This will tag the current branch and commit with this tag. Be aware what branch you are on and verify whether remote changes are still open to be pulled locally and possibly be merged. Doing a pull before tagging is in most cases wise.
Pushing a tag
git push --tags
That's it 😛