Never pierce the chicken before you start grilling it because the fat will drip out and catch fire. Use tongs and keep the chicken moving. If you do have a flare up, you can move the chicken to the upper rack or off the grill until the fire is out. You should cook chicken at a medium temperature, not on the highest heat.
It is best to turn the chicken pieces every ten minutes. Grilling chicken will take between thirty and forty minutes, depending on the size of the chicken pieces and the grill temperature. If you are using a BBQ sauce, add it about ten minutes before the chicken has finished cooking. Pierce the chicken and make sure the juices run clear. Alternatively, open one chicken piece. There should be no pinkness inside. Undercooked chicken can contain salmonella so it is important to always make sure it is properly done before serving it.
Unless you want to watch your chicken constantly to make sure there are no flare ups, you can opt for indirect cooking. If your grill has dual burners, you can preheat both sides then turn one side off and put the chicken on that side. If you do not have dual burners, you can make a pan out of aluminum foil and put it under the cooking grate with the chicken over the foil. The foil will catch the fat before it reaches the burners. This cooking method takes about ten minutes longer but you can leave the chicken for a few minutes to go and do other things.
You can always grill chicken with a rotisserie, using a low heat so the chicken cooks in the center before the outside is overdone. Rotisserie chicken is not the same as grilled chicken but the cooking principle is the same, as the chicken is exposed to a dry heat source and turned around until it is cooked.
Now you know how to cook chicken on the grill, you might want to invite some friends over for a barbecue! The most important things to remember are to coat skinless chicken, to keep skin-on chicken away from the flame and to make sure your chicken is completely cooked through before serving it.