01 - Rim the glasses with lime juice, then dip in coarse salt or sugar if desired.
02 - In a blender, combine watermelon cubes, lime juice, orange juice, and agave syrup. Blend until very smooth.
03 - Strain the mixture through a fine mesh strainer into a pitcher to remove pulp for a smoother consistency.
04 - Fill glasses with ice cubes. Pour the watermelon mixture evenly over the ice.
05 - Garnish with lime wedges and watermelon slices. Serve immediately.