Get GreaseMonkey for your browser.
Create a new script.
Choose an editor.
In the window, "New User Script" enter the following:
Name: WKD Hide
Namespace: http://*.wikidot.com/*
Includes: http://*.wikidot.com/*
Click OK.
You editor will pop-up.
Add the following at the end of the commented out section:
document.getElementById('navi-bar').style.display = 'none';
document.getElementById('footer-bar').style.display = 'none';
Save and Exit Editor.
Enable GreaseMonkey.
Go to any Wikidot site.
:-)
Kenneth Tsang (@jxeeno)