enter your new password, press enter and enter it again to confirm it
sudo passwd root
enter the same new password again, press enter and confirm it
now, if you like, you can open "System Preferences", go to "Accounts" and click the lock-symbol at the bottom left of the System Preferences dialog, authenticate with username: root and your new password and give YOURusernameYOUfoundOUT admin privileges by checking the "allow user to administer this computer" checkbox
you now have admin privileges with your user and the ability to add new users to the system, change all settings, install software etc.