To edit a page, just click on Icon(edit) or on the link "EditText" at the end of the page. A form will appear enabling you to change text and save it again. A backup copy of the previous page's content is made each time.
You can check the appearance of the page without saving it by using the preview function - without creating an entry on RecentChanges; additionally there will be an intermediate save of the page content, if you have created a homepage (Icon(home) is visible).
After editing pages, please leave the edit form by "Save Changes" since otherwise your edits will be lost!