In a zip-top bag, combine olive oil, fresh lemon juice, minced garlic, oregano, salt, and ground black pepper to create the marinade. Mix these ingredients thoroughly.
Add the chicken breast pieces into the bag, ensuring any excess air is removed before sealing. Gently massage the bag to ensure the marinade fully coats each piece of chicken.
Place the bag in the refrigerator and leave it to marinate for a minimum of one hour, up to a maximum of four hours. Prior to grilling, soak wooden skewers in water for approximately 20-30 minutes to prevent them from burning.
Thread the marinated chicken onto the pre-soaked skewers. Preheat your grill or grill pan. Apply a small amount of oil to the grill grates or the grill pan to prevent sticking.
Once hot, add the chicken skewers to the grill or pan. Cook for 3-4 minutes on each side or until the chicken reaches an internal temperature of 165°F (74°C).
Remove the chicken skewers from the grill or pan and allow them to rest for about 5 minutes before serving. This will help the chicken to retain its juices and remain moist.