Add all ingredients to a larger pitcher and stir until the lemonade powder has fully dissolved.
Serve in glasses over ice and garnish with small watermelon wedges.
Notes
If you'd like to make this ahead of time I suggest mixing all of the ingredients, except the fruit, the night before or the morning of when you'll be serving it. When it's time to enjoy just add in the sliced fruit!
For a tarter drink, add the juice of 1 1/2 lemons.