So what can you do when you want to make over a live site? There are three methods that work, depending on how confident you are with the technical side of things.MAMP/WAMP
This handy little open source project lets you install a web server on your computer, so you can create and run a WordPress website (complete with its own database) right on your home PC. MAMP runs on Apple computers, and WAMP runs on Windows machines, so there’s a flavor for everyone, and they’re both available as a free download.
They are a little on the techy side, though. So if you’re not comfortable with port numbers and databases, they might not be for you. The advantage of this method, though, is that your site will be completely unavailable to the general public, so no one will see it but you.
Development ServerIf you’re familiar with how subdomain works, then creating a development server will be a piece of cake. All you have to do is create a subdomain, such as test.yourdomain.com, and build your new site there. Once you’ve completed it, simply move the theme to the live domain and you’re ready to go.
WordPress Theme Test DriveThis handy little plugin lets you, as an administrator, see one theme, while your visitors see another. That means you can be working behind the scenes developing a new theme without anyone knowing the difference. You can download this plugin here:
One thing to note about Theme Test Drive, though: It’s not perfect. Your sidebar layout won’t work properly, for example, because the sidebars in your new theme won’t be named the same as the sidebars in your old theme. In addition, any relative links (those that don’t contain the full path to your site) that point to your theme files won’t work. So if your new theme calls it’s header with a link that looks like this /images/header.png you won’t be able to see the header in your test drive. That’s because WordPress will be looking in the wrong folder. Don’t worry, though, when you make your new theme live, everything will work as expected.The final way to develop a new blog theme is to simply put your site in maintenance mode. There are a lot of plugins that do a very nice job of that, and if you plan to complete your makeover in a day or so – perhaps over a weekend – that might be a good way to go. Again, when you’re logged in, you’ll be able to see your new theme, but everyone else will just see a “Down for maintenance” message.