#6. Don't Crowd the Grill
One of the most prevalent mistakes home cooks make when grilling is adding too many items to the grill and expecting good results. Tip #3 talks about creating grill zones for direct and indirect cooking, but there's no room for two zones if you overcrowd the grill from the start.
If you add too much to the grill and have a flare-up, there's no place to move the food. And let's face it; if you cook foods that start dripping fatty juices, you will have flare-ups.
No way around this, so you want to make sure you have a cooler part of the grill to move these foods over to.
Another reason to not overcrowd the grill is similar to not overcrowding a frying pan when cooking inside. The more you add to the grill, the more heat you remove from the grates. If you remove too much heat, the meats will steam instead of developing the desired grill marks, and the end results will be terrible.
If you don't have a big enough grill for a large group, cook in stages or borrow a neighbor's grill but be prepared to stay very busy at the grill.