Watermelon juice is a Ugandan comfort that I miss while stateside.
After hours spent on the dusty red road, there is nothing quite as refreshing as a cold glass of watermelon juice, freshly made, served with raw sugar and a spoon. I've always considered watermelon sweet enough alone, but sugar or honey can be added depending on your taste.
Cube the fruit from one large watermelon. Blend batches in a blender, adding a few ounces of water (and a few drizzles of honey, if you so desire) to the fruit before you blend. Strain through a mesh sieve. Serve on ice. Enjoy.
PS. Watermelon juice is also wonderful with a bit of a twist. See this recipe, here.