Here's a styleswitcher guide, I couldn't find a good enough one on the internet, so now I know, so I'm making one.
1: go to http://freewebs.com/pokecountry/styleswitcher.js and click "save". Save it on your desktop.
2: Go to your file manager and upload it to your site. Don't mess with it!
3: Go make a test page for the styleswitcher.
4: Put <link rel="alternate stylesheet" type="text/css" href="yourstyle.css" title="yourstyle"/><script type="text/javascript" src="http://yourhost.com/yoursite/styleswitcher.js"></script> right after the </title> in your html. Of course, replace yourstyle with what you want your style to be called, and replace htp://yourhost.com/yoursite with your site's URL. Remember: Your title must match the yourstyle.css. In other words, the yourstyle part of the code href="yourstyle.css" must be the same name as the yourstyle in the code: title="yourstyle".
5: Right after the <body> in your code, put: <link rel="alternate stylesheet" type="text/css" href="yourstyle.css" title="yourstyle"><link rel="alternate stylesheet" type="text/css" href="yourotherstyle.css" title="yourotherstyle"> . Again, replace yourstyle with the name of your styles.
Finally, put the code: <a href="#"
onclick="setActiveStyleSheet('yourstyle');
return false;">change style to yourstyle</a> anywhere in your site. This is the code for the part of your site for you to click on and change the style.
6: Then, repeat the process for new styles, such as "yourotherstyle". ^_^. E-mail me if you don't understand.
Remember to make styles! (make a page and rename it with .css at the end. Or you can upload a CSS file from your computer)