This page should show you what borders you have unlocked and allow you to select one to use.
If you want to get back to it in the future without a direct link, go to the wardrobe (in the drop menu under 'personal'), click the arrow beside 'personal' on that page, and select 'cosmetics' from the menu that pops up.
[font=times new roman]"There's no better vengeance than learning to enjoy again." [/font]