First you have to make sure that the an input type allows images. Usually, you have to add the image tag to the "full html" input type.
If you've done this and chosen "full html" as the input type of your post, then you're done.
But when you're using TinyMCE as your WYSIWYG editor, then you create an input type called "Rich Text" and you don't add any filters to it at all.
The catch is that, if Rich Text is not your default editing style, then, when you post a story, you have to remember to choose "Rich Text" as the "input type."
That's it. Please see the attached screencast.
If you've done this and chosen "full html" as the input type of your post, then you're done.
