1) Plants and Herbs
There are a number of herbs we use for cooking that bugs don't like in the wild. For now, set up small herb plants around the patio when you're entertaining. Mosquitoes stay away from basil or sage, and oregano repels most pests. If you are thinking ahead to next year, plan a bug-free fortress around your patio and grill. Wormwood keeps wasps and mice away, but it's a potent and poisonous plant that can also kill surrounding plants and is not recommended for significant human ingestion. Lavender, citronella, catnip, mint, and eucalyptus plants all fend off a number of bugs naturally. Their essential oils are also used to make bug repellents that can be applied directly on skin. Marigolds are also a great bug repellent and garlic and onions will keep rabbits away. You might not have the right greens planted this year, but keep this in mind as you're putting up your outdoor Christmas decorations and think about where you want your pest-repellent plants to go.
It seems counter-intuitive to have a fan on outside, but they generate enough wind to make it difficult for flies and mosquitoes to flutter. If it's too early to light candles, a couple of good fans can keep the yard bug free until dark.
You can't drape your entire backyard with mosquito netting, but you can at least cover your food. Keep your meals inside until you truly need them outdoors, but if you plan on setting up a buffet, there are a number of options to cover dishes. Smoke from the grill should keep bugs away from meat, but keep the meat and other food you plan on grilling refrigerated until you are ready to cook it.
Bugs love lights. There are a couple of theories on this. One is that bugs use the moon to direct them when they're flying at night. The other is that bugs use ultraviolet light to find holes to climb in at night. Either way, use light to your advantage. Use bug lights to draw insects away from guests when it gets dark. Add an extra layer of distraction and protection from the pests by placing them high above where guests are eating and drinking. Your company will thank you.
Citronella candles do double-duty to fight off bugs. Bugs hate the smoke given off from the candles and they also hate the smell. If citronella candles don't go with your DIY centerpieces or decorations, Mason jars and floating tea lights surrounded by bug-repellent herbs also make lovely preventative evening decor in the garden. Everyone expects some bugs at barbecues. Keep repellent on hand for the extra-sensitive guests, but these precautions will help keep the bugs at bay so you can enjoy outdoor entertaining.