1. Log in to cPanel, find the Databases section and click the phpmyadmin link.
2. Select your WordPress database. (If you're not sure which database to choose, check your wp-config.php file in the root location of your WordPress installation)
3. Select the 'wp_options' table (if you have another table prefix 'tableprefix_options')
4. Select page 2 of the table header.
5. You should now click 'Edit' to make changes to the 'template' and 'stylesheet' lines.
6. Enter the name of the template you want to assign to WordPress and press "Go" when you are done as below.
7. Repeat the same step 6 for the other rows and that's it. You've completed the changes. Maybe clear the cache and browse your WordPress site now to check it out.
