Please give us more information, so we can better assist you ;)I mean at which point do you struggle with the upgrade or don't you just know where to start?Beside that, as a little reminder, a release candidate should not be used within a productive environment.

This article though a bit outdated version wise covers the process.http://www.tmib.net/upgrading-osticket-1812-current-19rcAs a reminder RC releases are Release Candidates and should not be used in production environments.