First you need to create a global login account
here.
Once that is done you need to login by clicking on
Setup and then
Global Login Profile and then
Add Existing Profile and put your information in there. I suggest that you use the auto-login and remember password features.
After that, at the main menu click on
Play button then click on
Join Game and then click on
Update to get a list of servers and then pick one and click on
Play.
