In a large bowl, whisk the orange juice, soy sauce, brown sugar, and minced garlic together until combined. Reserve a 1/4 cup of marinade for later.
Place the steak cubes into the marinade. Refrigerate for at least one hour or up to 8 hours.
*If using wood skewers, soak them in water for 30 minutes before adding the meat and veggies. This will prevent the wood from catching fire on the grill.
Once steak is marinated, thread the steak, bell peppers, pineapple, and red onion onto the metal or wood skewers. Alternate the ingredients to ensure each kebab has a colorful balance of flavors.
Place kebabs on the grill to cook. Turn the kebabs while grilling (to ensure even cooking) and baste with the reserved marinade. Cook for 8 to 10 minutes or until the steak has reached your desired temperature.