Login to admincp, go to the style manager, hover over the style titles and notice the URL, copy and paste to view

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http://www.yoursite.com/forum.php?styleid=1
http://www.yoursite.com/forum.php?styleid=2
etc etc
OR
http://www.yoursite.com/forum/forum.php?styleid=1
So you can edit a template or remove the style selector from the footer and replace it with a few links for example if you don't have many styles by editing the footer as well and placing it with the other links

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