Please follow these steps for cloning your WordPress site ( E.g. site1.com to site2.com):
1) Create backup file for (site1).
2) After creating backup, download Backup File and Installer (install.php file)
3) Now create database for (site2) and add new user and grant all permissions to this user. Keep the information like Database name, User Name, Password handy.
4) Upload Backup File and Installer (install.php file) using any FTP program on site where you want to clone (site2).
5) Open your web brower and execute the install.php file -
6) It will display a form where you have to fill these details -
-New URL: site2 ( yoursite.com)
Then click the "Restore/duplicate" button
That's it - you have now successfully created a clone site.