Chapter 2 contains much information about many configuration options available in the configuration file. The Snort manual page and the output of snort -? or snort -help contain information that can help you get Snort running in several different modes.
In many shells, a backslash (\) is needed to escape the ?, so you may have to type snort -\? instead of snort -? for a list of Snort command line options.
The Snort web page (http://www.snort.org) and the Snort Users mailing list:
firstname.lastname@example.org provide informative announcements
as well as a venue for community discussion and support. There's a lot to
Snort, so sit back with a beverage of your choosing and read the documentation
and mailing list archives.