Go to https://bitcointalk.org/index.php?action=credit;promote
You will see a short page with instructions.
You need to send 0.0020833btc to a bitcoin address.
After you have done this and the transaction has 1 confirmation you can refresh the page.
Select Copper Membership from the dropdown menu on the new page and you are done!

By popular demand, newbies can now pay to have some of their restrictions lifted. If you pay the fee, you become a Copper Member, and you can post images. That's the main point of this: allowing newbies to post images. Additionally (and these might change depending on how things go), Copper Members currently have these bonuses:

- Some of the same permissions as Member-rank members, such as reduced signature styling restrictions. (But none of the PM-related restrictions are currently lifted, such as the style limit or per-hour PM limit.)
- Your "you must wait ____ seconds between ___" counter is reduced by 75%. So if you're naturally of Newbie rank, you only have to wait 360-75% = 90 seconds.