Checkout to your local repository.
git checkout firstname.lastname@example.org:miiicasa/yui3.git somefolder
git submodule add email@example.com:miiicasa/yui3.git somefolder
List all tag (go to somefolder):
git tag -l
git checkout "v3.6.0"
It will info you that the repository was detached from master.
You are in 'detached HEAD' state. You can look around, make experimental changes and commit them, and you can discard any commits you make in this state without impacting any branches by performing another checkout. If you want to create a new branch to retain commits you create, you may do so (now or later) by using -b with the checkout command again. Example:
Checkout as a branch:
git checkout -b "v3.6.0"