You can find instructions by expanding the "Wiki Text Directions" after you click Edit anywhere in the Wiki.  But if you have trouble getting started just click edit and add to what's there; create your own page by clicking edit and then just adding this to the bottom of what's there:

My Link

But put your own page title in place of My Link. 

You have to be a registered user on the site in order to post to the wiki; if you haven't already registered just click the Register link at the top-right corner.

You can upload files to share, too!  Just click the little Photo Gallery link to the right of the smiley face in the middle of the bottom row up at the top of the edit screen.

Also, if you have any requests regarding the functionality please post them here.