Okay, to post pics on a thread this is the way I do it, it might not be the easiest but it works for me.
Save your picture to your computers photo file and edit it to no more than around 600 pixels wide, I like about 350, and make sure you save it as a jpeg file not a bmp.
Start a thread, you will need to type in at least one word,
Below the message box click "go advanced"
then drop down until you see "manage attachments" and click there.
In the new window click on "browse"
select your picture and click "open"
repeat as needed
Then click "upload"
close that window,
then below the box where you found "manage attachments" click "submit reply"
now you are done, hope this helps