Bring Sustenance. It's not work if you're always getting up and going to the store to buy things, so plan ahead. Bring a big bottle of water, some sort of your favorite caffeinated product (if you drink such things—New York Magazine's Stefan Becket suggests ice coffee, as "working outside is the only acceptable instance in which you can drink iced coffee.") Also worth toting along are some easy-to-eat snacks, or even a bagged lunch. You are going to feel festive and get thirsty, but take it slow, for various reasons. As Tyler Coates, senior editor at BlackBook, told me, "Sit next to a cooler of Corona, and also drink slowly." Pace yourself.
You might consider bringing a friend or two, not because such a person is "sustenance" per se, but because sometimes it's more relaxing (and fun) to have another person around, you know, to watch your bag if you want to get up and stretch your legs. And bring your computer sustenance as well. Charge your laptop, your phone, or whatever equipment you plan to work on before heading out, and bring your chargers with you.
What to Wear. Dress appropriately for the weather—bare legs are O.K. when the degrees hit the high 60s, but bring a jacket or layers in case tree shade gives you a chill. Also dress appropriately for where you're going to be. If grass makes you itch, wear pants, or bring a blanket. If you burn easily, by all means, apply SPF before going outside (probably, you should apply it either way). "Sunglasses are key," says Becket. A hat might be good, too. Don't wear a puffy coat, unless you plan to nap in it, like a sleeping bag. A bikini or swim trunks may not be the best choice if you plan to set your laptop on your legs. Toasted leg syndrome is not a joking matter. Who wants to battle with that so early in the season? Oh, and if you have to go into the office afterward, consider that sarongs and short-shorts or jorts and a tank might not be your best work-to-work ensemble. Depending of course on where you work.
Think About WiFi. If you need to use the Internet, where are you going to have a connection? Many of New York City's parks, for example, offer free WiFi now, which is quite a boon for people who want to, say, blog in the out-of-doors. Before you leave the safety of your Internet connection, do some searching to find out where you'll be able to be online, and go to one of those places.
Partly Outside May Be Just as Good, or Even Better. It can be challenging to work in the full noontime sun while lying down on a blanket. Also, as Kerr points out, indoors establishments have their own benefits: "I work from a bar rather than a park bench or the beach because a bar has wine," she says. "Also I like having music on when I work, and it's nice to have people around since, when I'm not in a bar, I work from home and I start getting a little weird if I go too long without seeing other humans." She chooses a bar where the light shines in, and where there are sun-flecked tables outside. Picking a place where people know you as opposed to some random outdoor park spot can be beneficial, too: "The bartenders, and a goodly number of other regular patrons, know me and will watch my laptop when I go to the ladies room," she says. And she can plug her laptop in, if need be. Electricity. It's a wonder.