1.Put folder into userfiles/modules/shop/coupons 2.Create tables - cart_coupons - cart_coupon_logs 3.Add new columns on cart_orders table `coupon_code` varchar(255) COLLATE utf8_unicode_ci NOT NULL, `discount_type` enum('precentage','fixed_amount') COLLATE utf8_unicode_ci NOT NULL, `discount_value` decimal(10,2) NOT NULL 4.order_cart.php After Sub Total