Here is a recipe for making refreshing watermelon juice:

Ingredients:

• 1 small watermelon
• 1/2 cup of water
• Juice of 1 lime (optional)
• Ice

Instructions:

1. Remove any seeds and cut the watermelon into small cubes.
2. Place the watermelon cubes in a blender and blend until smooth.
3. Add water to the blender and blend again until well combined.
4. If desired, add the juice of 1 lime to the blender and blend briefly.
5. Pour the watermelon juice into a glass filled with ice.
6. Serve and enjoy your delicious and refreshing watermelon juice!

Note: You can adjust the amount of water depending on how thick you want the juice to be. For variation, you can add other fruits like strawberries or oranges to the recipe.