Start by cutting the watermelon into bite-sized cubes.
Slice the English cucumber and red onion thinly.
In a large bowl, combine the watermelon, cucumber, and red onion.
Drizzle fresh lime juice over the mixture and season with salt and pepper to taste.
Gently toss everything together to combine the flavors.
Chop the fresh mint and sprinkle it over the salad.
Crumble feta cheese on top before serving.
