The procedure explains how to edit articles from the back-end administrator interface in Joomla! 3.x

1. Log on to your site using the Administrator Login URL for your web site.
2. Find the article you wish to edit.
3. Click the title of the article to edit it:

Selecting article title in back end
4. Modify the text in the text area (see #1 below) under the formatting (WYSIWYG) toolbars as required.
5. Use the icons on the formatting toolbars (see #2 below) to format your text.  The function of each button on the toolbar will be displayed as you position the mouse cursor over it.  You can also find a guide to the functionality of all the editing buttons here.

 Editing article in Joomla! back end

6. When copying and pasting text from other applications, use either the Paste clipboard or the Paste as Plain Text clipboard.
7. When you're done editing your article, save it by clicking the Save & Close button to the upper left (see #3 above).
8. To cancel any changes you have made and close the article, click the Close button (see #4 above).