Administrator documentation
From MoodleDocs
Note for Contributors Let's concentrate on doing Documentation for Teachers first. We will move on to creating the docs for admins a little later. However, if you already would like to start creating content here, please, go ahead :-) You can start with creating a table of contents.
Installing or upgrading Moodle
Step-by-Step Installation Guides
If the Installation information above is not enough to guide you through the process, here are some detailed installation guides for different operating systems: