I have an up to date profile now. What do I do next??

You may have to reload the page - make sure your user name is showing in bold (blue on my browser) font.

When you hit 'reply' (or when posting a new thread) the message window should have 'Upload embedded file: Choose File (button) above the box where you type text.

Just hit the 'Choose file' button and navigate to the .jpg file in your computer. Try to resize your pic (software like Mihov Image Resizer or something more complex) to 800 pixels or so, and pick a resolution/quality that gets the image size around 100k-ish or smaller.