Show Payment Method in Admin Orders in WooCommerce

/* Show Payment Method in Admin Orders */
add_filter( 'manage_edit-shop_order_columns', 'add_payment_shop_order_column',11);
function add_payment_shop_order_column($columns) {
    $reordered_columns = array();

    foreach( $columns as $key => $column){
        $reordered_columns[$key] = $column;
        if( $key ==  'order_number' ){
            $reordered_columns['payment_method'] = __( 'Payment Method','Woocommerce');
        }
    }
    return $reordered_columns;
}
add_action( 'manage_shop_order_posts_custom_column' , 'orders_list_column_payment_title', 10, 2 );
function orders_list_column_payment_title( $column, $post_id ){
    if( 'payment_method' === $column ){
        $payment_title = get_post_meta( $post_id, '_payment_method_title', true );
        if( ! empty($payment_title) )
            echo $payment_title;
    }
}

Source: GitHub

If you want to know, by which payment method customer has placed an order on your site, use the above code in your functions.php.

Above code will add an extra column named ‘Payment Method‘ in the Orders Page in WooCommerce.