Here is a link to the "instruction manual" for this particular type of forum/bulletin board. This is good regardless of your skill level with using forums: http://www.phpbb.com/support/documentat ... /index.php
Learn the basics of editing your profile, sending and viewing private messages through the forum, posting and replying to forum posts, and everything else you need to know.
You can also see our Frequently Asked Questions section here: faq.php
If you take a look at the User Guide and still have questions, let us know and we will do our best to guide you.