For the vinaigrette, mix vinegar, salt, pepper and about 1 teaspoon sugar. Fold in the oil.
Cut the mozzarella into pieces. Cut melon into slices. Cut the flesh from the skin and remove the seeds. Cut the flesh into pieces. Wash, halve and stone the nectarines and cut them into slices.
Clean, wash, spin dry and pluck into large pieces. Wash mint, shake dry and pluck off leaves. Mix all prepared salad ingredients with the vinaigrette.