Once you have logged in with the editor or manager privilege, you will see some pencil-like icons located at the begining of every Text Edit Area (TEA).  Just click on the TEA icon and the corresponding area will open up for editing.

There are usually two Text Edit Areas on each page: the Page Heading and the Page Body (the content that you are reading now).  The Page Heading defaults to the "Topic Name" (the one specified in the navigation menu) unless you overwrite it with your own text.

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