Just three easy steps! Attaining the seller's savings and buyer’s twice convenience! Buy+1 is a multiple order system that links online shopping websites, linking Facebook and LINE message, +1 message method to automatically form an order. Simplifying order transaction process, provide the seller with three distinct advantages - time-saving, labor-saving, trouble-free benefits, while the buyer creates a convenient caller +1 for the customer, and the order is automatically set up – twice the convenience.