Soak your wooden skewers in water for at least 30 minutes, so they don't burn on the grill.
Chop your chicken into 1-inch pieces and add it into a large bowl. Add in the rest of the chicken ingredients (oil, vinegar, garlic, herbs, sea salt, and pepper) and toss well to combine. Let your chicken mixture marinate in the fridge for at least 20 minutes, or up to overnight.
Meanwhile, prepare your veggies then heat a grill pan or your outside grill on medium-high heat.
Next, thread one piece of chicken on a skewer, followed by onion, zucchini, red pepper, summer squash, and so on. Repeat until all the ingredients are used.
Grill your skewers for 5-6 minutes on each side, or until chicken is cooked through and no longer pink.
Garnish with freshly chopped parsley and serve hot.
Enjoy!