Modify your Hosts file in Windows XP, Windows Vista and Windows 7
Text entered into your Hosts file will be:
Where YourURL will be the actual web address for your new site. Once you have completed this process you should be able to view your site in your browser, Internet Explorer, Firefox, etc, by simply typing in the web address just as you would any other web site.
Remember to follow the same steps and remove that last line of code once the website is live.