Stars and Brand accounts can select one of their Websites or Paysites to become Promoted. You can do this for any of your current sites, in the Links tab in Settings. Each row you'll see will have a clickable dot on the right side.
Once you click the dot to the website you want and Save the changes, it will appear under every one of your posts, with the text "Click here to see my full content!", which viewers can use to go directly to your page.