Wiki 404 error - how do I create the Wiki page?

I missed a step in setting up my wiki. I followed the "Usage" instructions to set the settings, created my wiki, and made some categories. Then I added my wiki to my main menu. Now when I either click "Wiki" in my menu or click "View Wiki" in my dashboard I get a 404 error. Do I need to create a page for the wiki to appear on? I expected Wiki to generate its own pages. What should I do?