1. From the Sitefinity Dashboard go to Content > People

    Finding the People seciton



  2. Find the person you want to edit.  You can sort by the column "Full Name", or you can use the "Search..." box at the top of the page. 
    Click on the person's name to open and edit the listing.

    Search or sort



  3. Click on the "Contact Info" link in the section navigation on the left side of the page.  This will scroll the page to that specific section.   As you can see below, the email and office number are simple "fill-in-the-blank" text fields.  

    Updating contact info