First of all, you will have to register here:
http://support.morphos-team.net/
When you receive a login and a password, you could download all
official MorphOS updates.

You should start with PegasosBooks:
http://support.morphos-team.net/
This tutorial could be useful also:
http://www.korni.ovh.org/files/QuickGuide.lha

Good luck! :)