SharePoint (and Project Server) Shenanigans

After you have create your Enterprise Wiki, you might have a need to add additional fields. For instance, your client might want a summary field on the wiki page. In this case you will need to modify the Enterprise Wiki Page Layout. The video shows you how. Keep in mind that it’s not always a good idea to modify the Enterprise Wiki Page Layout. Instead it might be better to make a copy of the Enterprise Wiki Page Layout and modify that instead. If anything goes wrong with the copy and can simply start over.

Other helpful links:
Modifying the Page Layout for Enterprise Wiki Pages in SharePoint 2010
How to Create WIKI Custom Page Layout & Rich Text Control inside Your Page Layout?