To get a validation code for a McDonald's survey, start by making a purchase at McDonald's and keep your receipt. Visit the official mcdvoice.com survey website within the time limit printed on your receipt. Enter the 26-digit survey code found on the receipt, along with the required details like date and time of visit. Complete the survey by answering all questions honestly about your experience, including food quality and service. After submitting your feedback, you will receive a validation code on the screen. Write this code on your receipt and bring it during your next visit to redeem the offer.