Step 1. Find the picture you want to post in your flickr account.
Step 2. Press the "all sizes" button above the picture (See red arrow)
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Step 3. Copy the text from the part that says "Grab the photo's URL"
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Step 4. Reply to or start a new post on the Boxertrix Forum
Step 5. Type what you want to say
Step 6. Press the Img button once you should see [img] appear in your post
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Step 7. Paste the URL that you got from flickr in right next to the [img] dont leave any spaces.
Step 8. Press the Img button again to end the line [/img]
Thats it your picture should be displayed!![/img]