In a small saucepan, combine ½ cup of water with granulated sugar. Bring it to a boil over medium heat, stirring until the sugar fully dissolves—this usually takes about 2-3 minutes. Once dissolved, remove it from heat and let it cool completely.

Take 4 cups of ripe watermelon, cut into chunks, and add them to a blender. Blend on high speed until the mixture is completely smooth, usually around 30 seconds. Pour the blended watermelon through a fine mesh sieve into a bowl to strain out the pulp.

In a large pitcher, combine the freshly strained watermelon juice with the cooled simple syrup. Squeeze in the juice of 2-3 large fresh lemons and add 3 cups of cold water. Stir gently with a wooden spoon.

Cover the pitcher and place it in the refrigerator for at least 30 minutes.

Once chilled, fill glasses with ice cubes and pour the watermelon lemonade over the top. Garnish each glass with a wedge of watermelon or a slice of lemon.