Visit http://imgur.com , drag your image from windows onto the page, or click the computer button and select your image file:
Start uploading your image, it will upload and take you to it's page when it is done:
Copy the image's direct link like so:
In a post on the forums (new thread or thread reply) click the "Insert Image" icon:
In the textbox, paste your direct image link:
That's it, you're done!
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