Place the watermelon wedges on a clean cutting board and slice into thin, uniform pieces for even presentation.
Using a sharp chef's knife, peel the cucumber if desired and slice into thin rounds. Arrange the slices neatly on a serving platter or bowl.
Distribute the watermelon and cucumber slices evenly across the mixing bowl or directly onto individual serving plates. Sprinkle crumbled feta cheese over the top.
Drizzle olive oil over the assembled salad if desired, and season with salt and freshly ground pepper to taste. Toss gently to combine or serve as-is for a layered look.
Finish by inspecting the salad's appearance, ensuring the feta is evenly distributed and the ingredients are visibly fresh and colorful. Serve immediately for maximum crispness and flavor.