Flickr has been updated as of July 2010. Please use the guide here: Posting Photos from Flickr [July 2010 Update]
Visual Guides now available for:
Flickr (this post)
In case you're new to the forums or new to Flickr and you want to see how to post pictures using Flickr, here's a visual tutorial to try to clear up the steps.
1. Upload the photo that you want to use to Flickr and go to your Flickr page.
2. Click on the photo that you want to post in the forums and click on the "All Sizes" button.
3. Select either the small or medium size picture, then look for the text box that's under your picture. You see the text in box 1? Copy that text.
4. Come back to the forum and start a new thread or go to the thread that you want to post in. Paste the text from your Flickr page into your post and then submit your post or preview it and then submit it (combined into 1 step here since I can only do 4 pictures per post).