At forecourt:
You can show and tap your linked physical Hang Seng enJoy Card to use any redeemable Points, to the nearest 4,000 Points (i.e. HK$20). The maximum number of Points you can redeem in one transaction is 80,000 Points (equivalent to HK$400).
At Shell Select Convenience Store:
You can present the Shell Cash Voucher(s) QR codes you have redeemed on your yuu App to cashier upon payment.