In terminal, log into MySQL as root. You may have created a root password when you installed MySQL for the first time or the password could be blank, in which case you can just press ENTER when prompted for a password.
sudo mysql -p -u root
Now add a new MySQL user with the username of your choice. In this example we are calling it pmauser (for phpmyadmin user). Make sure to replace password_here with your own. You can generate a password here. The % symbol here tells MySQL to allow this user to log in from anywhere remotely. If you wanted heightened security, you could replace this with an IP address.
CREATE USER 'pmauser'@'%' IDENTIFIED BY 'password_here';
Now we will grant superuser privilege to our new user.
GRANT ALL PRIVILEGES ON *.* TO 'pmauser'@'%' WITH GRANT OPTION;
Then go to config.inc.php ( in ubuntu, /etc/phpmyadmin/config.inc.php )
/* User for advanced features */
$cfg['Servers'][$i]['controluser'] = 'pmauser';
$cfg['Servers'][$i]['controlpass'] = 'password_here';