- Wash the watermelon under cool running water and pat dry.
- On a cutting board, place the watermelon on its side and cut it in half from side to side. Hollow out both halves of the watermelon with a spoon or scoop, reserving the watermelon pieces to dice up for serving.
- Apply fruit rollup strips to the best looking watermelon half and secure with toothpicks to appear like sections of the helmet. Decorate the fruit roll up strips with blueberries attached with toothpicks if desired for added details.
- Trim a small piece off each banana and secure with toothpicks on each side of the helmet. Use a dry erase marker on scraps of rind from the other half of the watermelon to make a point for the top of the helmet or to form horns if not using bananas.
- Use the other half of watermelon as a bowl and fill with watermelon cubes or fruit salad & serve.