Web Forum Structure Development -Searching for a Documentation Template

[vesnianka]

Hi! Ok, don't laugh. I was asked by a client to develop a web forum, in structure and content. My question is, how do I document the structure of a forum, for my client? Is it done as a site map? a mock-up? a diagram? Does anyone have a template that I can use, to customize how I would like the structure of the forum to look? Any ideas, pointers or professional recommendations? I am looking for formalize this process.

Thanks so much!