Watermelon Juice:

1. Place all the ingredients into a blender and blend on high until smooth.
2. Strain into a bowl through a fine-mesh strainer (optional but recommended).

Watermelon Coconut Rum Cooler:

1. In a tall glass, combine the coconut rum and agave syrup and stir to combine.
2. Top up with ice and pour in the watermelon juice. Add a slice of lime and a few mint leaves for decoration.
3. Hold the glass on an angle and slowly pour in the sparkling water over the ice to the top (this creates the ombre effect)
4. Serve decorated with a small watermelon slice or lime and some mint.