16 Tips for an Effortless Outdoor Party

The three things to include on the invitation:

When they’ll be eating. Avoid refiring the grill for latecomers with something like “The grill master will be slinging grub from 6 to 7. Come and get it!”

Attire. Everyone (OK, every woman) is wondering what to wear. Tank top? Sundress? Give guests a sense of the vibe: “You wear the flip-flops; we’ll flip the burgers” or “Bring your swimsuits!”

Rain plans. “I don’t think you need a rain date unless it’s a 600-person church picnic,” says Clark. “A 30-person barbecue at my house is going to happen no matter what.” But if you want to clarify, add a note: “Rain or shine.” Or “If it rains…game night inside!” Just be sure that you have room for everyone in your living room.

What if you have five patio chairs and 25 guests? Assess your indoor furniture. The easiest option is to press dining chairs into service, along with any drum stools or poufs. If you’re keeping things casual, you can spread pretty quilts on the ground and let people gather picnic-style.

Renting can be another surprisingly cheap way to go. Folding chairs start as low as $2 apiece. (You may also be able to rent coolers, speakers, tableware, and a bigger grill.) Many vendors will even drop off and pick up, so all you have to round up is the guests and good cheer.

Is that your dog Sparky? Or a skunk? Don’t leave guests in the dark. All you need is a little ambient lighting, says Jimmy Duhig, the owner of Creative Lighting Design, in San Francisco: “If you’re outside while it’s getting dark, your eyes will adjust.” Just hang strings of lights on the deck, the fence, even tree branches, and add some hurricane lanterns or tealights. Duhig recommends globe string lights, elegant round bulbs that give off a warm glow (try Room Essentials Clear Globe Lights; $15, target.com). “This is what you always see strung overhead at outdoor dinner parties on TV,” he says.

What to do with extension cords (a.k.a. trip wires) If you need to run cords through the yard, says Duhig, snip old wire hangers with a wire cutter and bend them into skinny U-shaped pegs (like croquet wickets, but only an inch or two wide). Then arc them over the cords and hammer them flush into the ground.

In fact, you really only need one party decoration (hint: it’s a pinata). It’s colorful! It’s interactive! It’s wise to hand out the broom before everyone has had three margaritas! Buy a big piñata that fits the mood of the fiesta (try orientaltrading.com or confettisystem.bigcartel.com). “Fill it with dollar-store items in one color. Monochromatic always looks chic,” says Calder Clark. “Buy things people can wear, like sunglasses and necklaces. It will make fun photographs.” Other festive loot: lottery tickets and—especially for a pool party—mini water pistols.

Tricks for preying on their weaknesses:

Get rid of standing water. “That’s where mosquitoes breed,” says Laura Harrington, an associate professor of entomology at Cornell University. “The week before the party, empty out the kiddie pool, the rain gutters, and any rainwater that has collected in the bottoms of flowerpots.”

Plug in some fans. “Mosquitoes are weak flyers, so even if a fan is set on low, it can create enough airflow to keep them away,” says Harrington. This works best in a small area, like a deck, where you can set up two or three box fans around your guests. It’s also a good idea to put a tabletop fan near the salads.

Offer guests bug wipes that won’t create a smelly fog. “Look for products that contain the repellent picaridin instead of DEET,” says Harrington. “DEET can degrade synthetic fabrics, damaging clothing.” Try Skin So Soft Bug Guard Plus Picaridin Towelettes ($14 for eight, avon.com); stash them in a basket by the back door. You might also consider a bug-repellent gadget for the yard; for the most effective options, see The Best Insect Repellent Options.

Playlist tips from Michael Antonia, the owner of the Flashdance, a production company in Los Angeles.

Don’t crank the speakers. No one will want to stand near them if they’re blaring. The best setup is four or more speakers, spread out, set at a lower volume. “If you’re using a boom box or an iPod dock, place it above ear level so it’s not blasting directly at guests’ heads,” says Antonia. “And turn it toward the side of the house—you can make it a little louder and the sound will spread out better.”

Go heavy on classics: the Rolling Stones, the Beatles, Stevie Wonder, Michael Jackson—songs that people recognize. Keep it upbeat, and mix in some newer tunes here and there. “I like Bon Iver, Beach House, White Stripes, and Elliott Smith,” says Antonia.

Plan for five hours. “Most parties aren’t going to last longer than that, and if there’s anyone who realizes the playlist has started over at hour six, well, they probably need another drink.”

So the grown-ups can kick back with the sangría, have some diversions for the kids: plenty of blowing bubbles, perhaps a sprinkler or a Slip ’n Slide, and beach balls. You can also buy a few inexpensive disposable cameras and let kids serve as official event photographers.

How to survive the sweltering heat:

Handheld fans. Natural raffia fans or classic accordion fans (both available at orientaltrading.com) look pretty placed in big baskets.

Ice-cold compresses. Buy a pack of inexpensive washcloths from a dollar store, roll each up and secure with a rubber band, then toss into a cooler of ice water for guests to grab. (The best cooling points are the neck and wrists, where large arteries run close to the skin.)