Have the watermelon at room temperature when you carve. The cuts will be easier to make. You can chill the watermelon in the refrigerator after cutting and before serving.
After you’ve drawn the design on the rind, insert toothpicks in key places to use as guides for your cuts. Use a sharp knife with a pointed tip – the sharper the knife, the easier and cleaner the cuts will be.
When attaching cut pieces on the watermelon to make your design, use round toothpicks or skewers. Flat toothpicks will often break due to the weight of the piece or the thickness of the rind.