schedule_wp_cron_event.php

<?php

/**
 * On an early action hook, check if the hook is scheduled - if not, schedule it.
 */
function prefix_setup_schedule() {
	if ( ! wp_next_scheduled( 'prefix_hourly_event' ) ) {
		wp_schedule_event( time(), 'hourly', 'prefix_hourly_event');
	}
}
add_action( 'wp', 'prefix_setup_schedule' );


/**
 * On the scheduled action hook, run a function.
 */
function prefix_do_this_hourly() {
	// do something every hour
}
add_action( 'prefix_hourly_event', 'prefix_do_this_hourly' );