To receive a McDVoice survey invitation, you need to make a purchase at a participating McDonald's restaurant. Keep your receipt, as it will contain a survey code or store number required to enter the survey. Visit mcdvoice.com survey within seven days of your purchase and provide feedback about your experience. Once completed, you may receive a validation code for discounts or free items on your next visit. Make sure to follow the rules and limitations, as there is a limit to the number of surveys you can take per month per restaurant.