This post will explain how to post one of your photos hosted on flickr to this website. This may be applicable to other photo hosting websites that have similar options.
Step 1. Go to the photo page on flickr
Step 2. Choose to share the photo
Step 3. Choose HTML, the size should be medium 500 and the button at the bottom for html should be chosen as well
Step 4. Select and copy the link given which should look like this:
<a href="Page Link" title="Page Title"><img src="image link" width="500" height="400" alt="image title"></a>
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Step 5. In your forum post whether a reply or a new topic add this link to the body
Step 6. Hit Preview you should see your photo in your post
Step 7. Review your post and save and you will see your topic or reply post to the forum.