Yes, you can make a fruit platter the day before serving. In fact, preparing the platter in advance can save time and make it easier to plan for an event. However, some fruits may not hold up well overnight, especially if they are sliced or cut. Fruits such as apples, pears, and bananas can start to brown, while others like grapes and strawberries can become mushy. To prevent this, you can treat the cut fruit with lemon juice or a mixture of lemon juice and water to slow down the browning process. You can also store the cut fruit in an airtight container in the refrigerator until you are ready to arrange it on the platter. Just be sure to give the fruit enough time to come to room temperature before serving to ensure the best flavor and texture.