Login or register here, then go to this link and click “get Cashback”. It will send you to the Walmart website, where you have to purchase the 40 fl oz bottle of Tide laundry detergent for $3.97 with free in store pickup. Within a week or so your TopCashBack account you will be paid $3.97(or $4.08 if you opt for an Amazon gift card or AMEX gift card), making it Free. The purchase at Walmart must must only contain one 40 fl oz bottle of Tide laundry detergent for $3.97