Planning the development of a forum - advice

[Barça]

Ive got a plan to make a forum site for Language teachers. I have a simple understanding of html and some basic css and very very basic php.
OK, I think its gonna take me a good few months to get it all designed, the options for forum software (not havin to pay) are phpBB or SimpleMachines.
At the moment I know very little about the creation and difficulty of using these packages but I wonder if you can help. I'd like a nicely designed (CSS) site which uses one of the above forum softwares. Can anyone point me in a direction for looking at how to plan the developments of the site and how to work with CSS and forums? Any websites you can recommend? Is it right to make the design first in CSS, then incorporate the forum? Or does the forum software not need CSS? Possibly rather naïve questions at the moment, but hey, it's all about learning, right!

[grahame]

One of the best ways for you to learn and plan is for you to try it out. Download and install copies of SMF and/or phpBB in some unlinked corner of your web space and try it out. That way you'll learn the basics and see how the design of the site hangs together far quicker and more easily that by just talking or reading about it.