Use the knife and cutting board to cut the watermelon into manageable chunks, approximately 1-inch pieces. Ensure the seedless parts are removed for a smoother blend.
Add the watermelon chunks to the blender, followed by the freshly squeezed lime juice and coconut water. Secure the lid tightly on the blender.
BABlend on high speed until the mixture is completely smooth and frothy, about 30-60 seconds. Stop occasionally to scrape down the sides if necessary. The texture should be uniform with no chunks remaining.
Once blended, turn off the blender and briefly tap to check the consistency. The smoothie should be vibrant pink, slightly opaque, and have a chilled, refreshing appearance.
Pour the smoothie into glasses and optionally garnish with a small lime wedge or a sprig of mint. Serve immediately for the best cold temperature and fresh flavor.