To redeem McDonald's prizes, first complete the mcdvoice.com survey after your purchase. You’ll need a valid receipt with a survey code. Visit the website, enter the code, and answer all the questions honestly. Once completed, you'll receive a validation code. Write this code on your original receipt. Bring the receipt with the code to a participating McDonald’s location during your next visit. Present it at the counter to redeem your prize, which could be a discount or a free menu item. Always check the expiration date and terms mentioned on the receipt to ensure eligibility and avoid missing out.