Im going to assume that you will be making some of the most common mistakes before manning the grill. Also, I am addressing you. Not the general sense of you, but I am actually addressing you. You were going to mess up the food this weekend weren't you? You were. I know it. You know it. Nana knows it. I bet you were going to mess it up in the following ways:
1. You were going to use a gas grill. Why on earth would you do that? You know where natural gas comes from? Russia. Why would you spoil America's Independence by using Russian gas to cook your food? Rude.
Gas grills have no place in the backyard. If you want to cook with gas, stay in the kitchen. Coals. Coals are what's needed for backyard, beach, and lake front cooking. Something is special about the taste of charcoal on food. It tastes like freedom. There is no better weekend to taste freedom than July 4th weekend.
2. You were going to start your coals with the aide of lighter fluid. Dammit. No. Don't do that. There is plenty of good options out there where you don't need to add lighter fluid to your coals. Get a chimney. Get these little wax candle shits. Get one of these little things and change your life. Whatever you do, don't use lighter fluid.
3. It's not a shortcut around the no lighter fluid rule to use match light coals, so don't you even think about it. What's your problem? Seriously.
4. Stop using the "it looks done" method. Meat is done with the internal temperature says that it's done. Look up the times for your specific meat, because going under the minimum can make everyone sick, and going over the desired range can dry your food out. Remember that once you take the food off, the temperature will continue to rise.
5. You weren't going to let the meat rest were you? You weren't. No matter what the cut of meat is, let it rest for a minimum of 15 minutes. Most grilled or barbecued meat is better when it has rested for at least 30 minutes. You can cover the meat in foil if you are really worried about it getting cold. It wont get cold, though. The juices in the meat will redistribute and you wont have piles of flavor and juiciness leaving your meat.
6. Dont just take the meat from the fridge and throw it on the grill right away. Take the meat out of the fridge about an hour before you want to cook it. Let the meat come to room temperature and then put the meat on the grill.
Also, don't be the guy confusing grilling with barbecuing. They are completely different. Grilling is not the same as barbecuing.
If you want some more tips about the specific meat that you will be cooking, hit me up on twitter at @unclechaps. I'll be around all weekend and would love to help. Other great BBQ and Grilling sources are @Paulheels, @alfiebcc, @jagschef and @pile_of_derp.
Dont cook like a dickhead, dickhead.