This tutorial will teach you how to login to Joomla as the default administrator. You should have your Joomla administration login page open in your browser. If this is your first time logging in as the root administrator, the default username is admin. Enter the password you created during installation. Click Login. You are now logged in to Joomla as admin, on the admin panel. You may wish to change your password after installation or on accasion to increase security.
On the right hand side, in the list of logged in users, select admin from the list. This will open a new User detail screen where you can change you password and verify it if you choose. Click Save when finished.
Once you are done in the admin control panel you will need to logout. Scroll right. Click on Logout in the very upper right hand corner.
That's it. You now know how to login to Joomla as admin, change your password and logout.