Initial installation

Hi. From looking at this forum I get the sense I’ve bitten off more than I can chew…

I run theswanseaway.co.uk, and am trying to activate the bbpress forum. I’ve set it up so you can see the forum at theswanseaway.co.uk/forums, but the problem is there’s no link for people to sign up? Also it’s shortened the menu tab so that the “about” section has dropped to form the start of a second row.

I have read about using custom templates, but I haven’t messed with html much in the past and I’m wary of “breaking” the current site, as it were.

Is there a walkthrough anywhere online which can show me how to make the forum functionable?