This is how I prepare my production environment for my rails applications.
(!) DO NOT FORGET mysql_secure_installation
CREATE USER 'newuser'@'localhost' IDENTIFIED BY 'password';
CREATE DATABASE `databasename`;
ALTER DATABASE `databasename` CHARACTER SET utf8 COLLATE utf8_general_ci;
GRANT ALL PRIVILEGES ON `databasename`.* TO 'newuser'@'localhost';
FLUSH PRIVILEGES;