The easiest way to create a MySQL database is to use the "MySQL Database Wizard" in cPanel.
You can access cPanel by logging into Member Zone, and clicking on the "Access Site Admin Panel (cPanel)" link. If you're logging into your Master Account, you will need to click on the domain name first before you can see this option.
Once you're in cPanel, scroll down and you should see the "MySQL Database Wizard" icon. The MySQL Database Wizard will guide you through the database creation process.