Click on Photo Gallery on the top menu
Click on Upload Photos (on the right)
Select a Gallery for your photos from the dropdown
Below that there are 10 blank spaces with a Browse button to the right of each one.
Click it and navigate to the folder on your computer where your image(s) are stored.
Select one and repeat as needed.
Enter a title, description and keywords (for searching) and hit Upload/Submit
At the next screen fill in any optional details and hit Process.
When it finishes you should now see your photo in the gallery you specified
Click on the photo for details about it.
There's two buttons that say copy to clipboard under the photo.
Copy and paste the code in the linked thumbnail box to make a clickable thumbnail in your post:
Copy and paste the code in the BB Code box to insert the image full-sized in your post:
From any external website or photogallery the code looks like this:
[img]http://www.website.com/image.jpg[/img]
If you're still stuck, shoot me a PM for my phone # and I'll walk you through it. I'm local, and your AZScuba moderator...