This is a step-by-step guide for properly setting up a custom domain.
First, click on the My Services tab. If it says that there are no available services, then you must do the following:
Click on My Domains
Check the box by the domain you are using with WikiSpot.
Click on the drop-down menu in "Step 2: Select Domain Management Task".
Select "Add Services" for selected domain. Press "Go".
On the next screen, click on the "Domain Tools Bundle" to add it to your cart. As of writing this guide, it is free. You will not be charged.
On the next screen, ensure that "Domain Tools Bundle" is listed to the right, review the service agreement, decided whether or not you agree to it, and click on "Complete Order".
You may now return to domain management and click on the My Services tab.
Find the row that represents the "Canonical Name" or CNAME. If you want the wiki to be available at www.yourdomain.com, take a look at the following screenshot. Note that www can be replaced with anything else you desire. Click Update and you'll see the a new CNAME entry.
Click on the My Services tab, then click again on "Manage" next to the appropriate domain.
Scroll down to the bottom and look for URL Forwarding. Click "Manage".
Update your domain's DNS servers as specified on the page where you edited your CNAME. As of writing this, they suggested the following DNS servers:
At least, you should be. The writer of this guide couldn't actually test if the procedures worked. Do change this paragraph if it does!