Ken,
Although I know a fair bit of 'what' and 'why', about websites, I'm a bit light on 'how' since others have tended to do the doing in projects that I have managed or participated in. However, I do know that for most websites, the forum module is an add on which you download and add to your site. Wix has a store of add on modules of all types and I found a free social forum 'app' see:
http://www.wix.com/app-market/social-forum/overview and
http://www.wix.com/app-market/allSince you have been able to get the NAZ website going, I don't think that adding a module can be much more difficult. I have done this on Wordpress once and it was easy.
I can't find the date on the site you refer to in your last post, just suggestions on website of a week in September when an event might occur. For your average busy person even we retirees, you can't really plan on anything on so vague info. Does it encourage people to write in for details? Possibly, and it's generally a good ploy to have 'calls to action' to get people to interact with the site. However, for my call I would say you need to plump for dates first and be specific. Advertise date, time, location and what will happen, Here are a couple of fictitious ones as an example of what I mean:
> 12th September - Walk in the Wilderness. A guided group walk from 10am-4pm. Easy Strolling conditions, hills less than 20%. Stops for lunch and other breaks Bring own food. Mail me on or before 9th September for map and start point. All welcome. Cost: Free
> 19th September - Nude Music evening. Social gathering CO for music lecture by naturist composer Ken Walkland. Tunesville AZ 8pm
Mail me on or before 18th September for location. All welcome. Cost: $10, Coffee & Cake $5
Many people believe that putting their stuff out on the web or social media is the thing that attracts people, and that's all they have to do. It isn't. You can do all the SEO you like but if someone isn't searching for terms that are relevant to your site, they won't find you. I think you need to do a bit of SEO, Ken. I googled various terms like Arizona Naturism, Naturists Located in Northern Arizona, picking copy off your website. I googled Naz2 and Naz2 naturists. None of these brought the site to the 1st page. Only 2 searches worked - Naz2 Arizona and kensunwalker. But these are very specific - who would know specifically what they are looking for in advance? - That's not a search.
What I think would be good to do is to spread the word of your site and get people you know to visit it, spread the word, chat about it on social media and get their friends to visit. That's how websites get accessible- by advertising them on other areas than the web.
One very good source of info on how to add a forum would be our own Stuart & Karla who added the very forum we are using to their website (i.e. this one!). Stuart? Are you there?
Anyway, Ken, I hope that's useful, if slightly challenging info and I hope the website and Naturists of Arizona takes off in the manner you want it to.
John