You have to become a premium member on the Forum first. I think it is $25 for the year. There should be a link at the bottom of the page, though I'm looking at this on my phone and can't give you a direct link.
If you go to the black section at the bottom of the page and look under the blue discover heading. There you will see a sub heading for premium membership. Click on that and it will take you through joining as a premium member.
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