If using wood skewers place them in a shallow dish with warm water and fully submerge them for at least  30 minutes before using them. 

Cut your chicken up in to uniform 1 inch pieces and place in a large bowl with a lid or in a zipper topped bag.

In a small mixing bowl add the soy sauce, olive oil, vinegar, brown sugar, Worcestershire sauce, and garlic powder. Stir well to combine.

Add the marinade to the chicken in the bowl or bag and mix to combine everything well. 

Place the chicken mixture covered in the fridge for 30 minutes or up to 4 hours. 

When you are ready to make your kabobs, thread the skewers evenly with pieces of chicken.

Preheat your grill to medium to medium high heat (375 degrees F to 425 degrees F). 

Clean and oil the grates (I do this with a cleaning brush and then I dip a paper towel in oil and rub it on the grates with tongs; this helps everything to not stick).

Place the kabobs on the grill and cook, turning occasionally, until the chicken is cooked through and the internal temperature reaches 165 degrees F on an instant read thermometer, about 15 minutes (start checking the temperature at 12 minutes).

Remove from the grill and allow the meat to rest for 3 minutes.

Serve right away.