There are default settings for the font style and size. That means we can just change the default and then all the text in the website that has not been manually formatted will conform instantly.

To change the text size default, follow these directions:
 

1. Go to the admin menu, site settings
2. Expand the StyleSheet Editor
3. Find the style named .Normal {}
4. If there is no style named .Normal - then create one. Use the example in number 6 below.
5. Enter the following in between the brackets:   font-size:12;
6. You now have
   
   /* text style used for most text rendered by modules */
   .Normal
   {
   font-size:12;
   }
    
7. At the bottom of the Stylesheet editor, click “Save Style Sheet”

You’re done. All the text in the site will now be the new size of 12. If you want that to be larger, change 12 to 13 or 14. Remember to save the style sheet each time.

Note: Any text that you have manually formatted to be a particular size will not be influenced by this change in the default. To restore that text to the default, you need to highlight the text, and use the eraser to remove the manual formatting.