If a customer receives the wrong size from Bigdogs.com, it is recommended to first review the return and exchange policy available on their website. Typically, customers can initiate a return by following specific steps outlined in that policy. Usually, the customer will need to have the original packing slip and the item must be returned in its unused condition. Instructions for printing a return label may be provided on the website, facilitating the return process. After the return is processed, customers can select the correct size for exchange, depending on the availability of the desired size. For specific questions or issues encountered, the website generally offers contact information where further assistance can be obtained.