How to render custom post meta in admin table

I created an Events custom post-type. I added the columns to the admin table view like this:

function events_cpt_columns( $columns )
{
    unset(
        $columns['date']
    );

    $new_columns = array(
        'event_date' => 'Event Date',
        'event_location' => 'Location',
    );

    return array_merge($columns, $new_columns);
}
add_filter( 'manage_events_posts_columns', 'events_cpt_columns' );

How can I render the values too? The rows are kept empty for some reason.