Method 1: Edit file .htaccess:
Add the following to .htaccess (Make sure you back up .htaccess before you edit it):
php_value max_execution_time 300
Method 2: Edit file wp-config.php:
Add the following to wp-config.php:
set_time_limit(300);
Method 3: Editing php.ini
Add the following to php.ini:
max_execution_time = 300
Read more about Maximum execution time exceeded on WordPress.org.
