Best way to install Discourse on my server?

I think it’s about time I get a Discourse forum up in production, but I’m not sure which method will be best for me and my server, which is running…

CentOS 6
Virtualmin
Apache
Passenger
Postgres
Latest Ruby, various gems etc

I currently have several sites on the server, some are PHP (forums) and some are Rails apps, and until now they have all lived happily together, and I’d like to add Discourse to tha family without sacrificing any of the features I currently enjoy (like being able to easily set up emails for each domain, etc).

Any idea what’s the best way to get a Discourse forum on my server please? (And hopefully at some point, several Discourse forums!)

I don’t mind installing software and configuring things if that will mean I get the best performance.