Cut your watermelon fruit pulp from the skin. Avoid adding the white tasteless pulp to the fruit pulp.
Place watermelon chunks in a food processor. You can add sugar and/or salt or a spice or herb of your choice to flavor your watermelon juice (see post for variation ideas).
Blend to a smooth consistency.
Place a large thin strainer on a bowl. Pour some of the fruit juice into the strainer.
The juice will drop into the bowl and seperate from the mash and seeds.
Press out remaining juice from the pulp with a silicon spatula or spoon. Discard dry-pressed pulp (I add it to my mud and plants when planting something).
Strain and repeat the process with remaining juice.
Serve up cleared watermelon juice as is or with ice cubes.
Notes
This is a low-calorie, gluten-free, vegan-friendly recipe. It's also sugar-free if you skip the sugar part.