Put all files into your magento root folder.
The extension is modman enabled. If you use modman you can deploy it easily.
After installation you must enable the yubikey authentification for admin users.
Go to “System → Configuration → Admin → Yubikey”.
Enable yubikey. You can alternativly define your own yubikey server or disable HTTPS communication (not recommended).
You must enter the client id and the secret for you magento shop.
If you need a client id you can register it at https://upgrade.yubico.com/getapikey/
You need an yubicode to get the client id and secret.
If you had problems with yubikey authentification there is a option to enabled logging. The service now loggs the
return status from yubikey service and the one time password to var/log/yubikey.log
After enabling the yubikey service you must add a yubikey ID for each user. Open “System → Permissions → Users” and
select the user.
The user edit form has a new tab to configure the yubikey. Add a yubikey to the user. Please note that you can
block yourself if you assign a wrong yubikey id to the current logged in user!
If you did this you can reset the yubkey id on the database. There is new field “yubikey” in the the table “admin_user”.