Wash all the vegetables thoroughly.
In a large bowl, add the mixed greens.
Slice the cucumber and add it to the bowl.
Dice the tomatoes and incorporate them into the salad.
Thinly slice the red onion and add it on top.
Sprinkle the Kalamata olives over the salad.
Add the cubed feta cheese for a creamy texture.
In a small bowl, whisk together olive oil and red wine vinegar.
Season the dressing with salt and pepper to taste.
Drizzle the dressing over the salad and toss gently.
Garnish with fresh oregano before serving.