By far the easiest way is to just attach files to your post. Next time you post, scroll down to the bottom of the page below the text editor, and there is a "browse" button which will allow you to select a file (picture) to add. The trick is to make the picture a size that is acceptable to this forum. I wrote something up on how to do that here:
viewtopic.php?f=11&t=24099If you run into trouble doing that, or have specific questions about doing it the hosted picture way, let me know. I'm usually pretty good at figuring such things out (computers love me).