Cut rind from the watermelon and chop the fruit into 1-inch cubes.
If using a watermelon with seeds, while cutting into cubes, remove the seeds: this becomes a very labor intensive effort and a seedless watermelon is highly recommended.
In a small bowl, whisk together olive oil, lime juice, salt and pepper; set the dressing aside.
In a large bowl, combine watermelon cubes, crumbled feta and basil leaves.
Toss gently until ingredients are combined well.
Transfer to a serving bowl.
Sprinkle a few basil leaves on top.
Drizzle the dressing over the salad.
Stir gently to integrate the cheese and dressing into the salad.
Always serve chilled.