Chill the watermelon cubes in the refrigerator before assembling.
Place the watermelon pieces in a large mixing bowl.
If excess juice collects, gently drain before adding feta.
Sprinkle crumbled feta cheese evenly over the fruit.
Add roughly chopped fresh mint leaves.
Season very lightly with pepper and add salt only if needed after tasting.
Toss gently using a spoon to combine.
Taste and adjust seasoning if needed.
Transfer salad to a serving bowl.
Serve immediately after tossing to maintain crisp texture and fresh flavor.