Prepare four 12-inch wooden skewers.

Place the shrimp in a large resealable plastic bag.

Add 2 tablespoons of olive oil, oregano, crushed red pepper, grated garlic, lemon zest, and lemon juice to the bag.

Seal the bag tightly and massage the marinade into the shrimp.

Marinate the shrimp for 15 minutes at room temperature.

Preheat a grill or grill pan to high heat.

Combine watermelon and cucumber in a mixing bowl.

Top with feta and olives.

Scatter most of the mint over the watermelon mixture, but do not mix.

Thread about 5 shrimp onto each skewer.

Brush the cut sides of the baguette halves with 2 tablespoons of olive oil and season with salt and pepper.

Place the bread cut-side down on the grill along with the shrimp skewers.

Grill the shrimp until lightly charred and cooked through, about 1 to 2 minutes per side.

Grill the bread until lightly charred, about 2 minutes.

Remove the shrimp and bread from the grill.

Rub the cut sides of the halved garlic onto the hot bread.

Halve each piece of bread again and place one piece on each of four serving plates.

Add the remaining 1/4 cup olive oil and a pinch of salt and pepper to the salad, gently stir, and divide among the plates.

Top each serving of salad with a shrimp skewer.

Garnish with the remaining mint and serve immediately.