Cut the tomatoes into wedges, and if any are large, slice them again into bite-sized pieces.
Partially peel the cucumber for a striped pattern, cut it in half lengthwise, and slice into half-moons about 1 cm thick.
Thinly slice the red onion into half-moons.
Core the green capsicum and slice it thinly into strips.
In a serving bowl, place the tomato wedges at the bottom, followed by the cucumber, onion, and capsicum slices.
Scatter the Kalamata olives on top. Drizzle the salad with olive oil, sprinkle with salt, and most of the oregano (keeping a little aside for later), then gently toss to combine.
Place the block of feta cheese on top. Drizzle a little more olive oil directly onto the feta and sprinkle with the remaining oregano for a final touch.