TRAVEL INSIDER : Knowing What to Take When You Hit the Road : Packing: Veteran globetrotters share the items they wouldn’t travel without--from eye masks to nail glue.

It’s departure season. The U.S. Travel Data Center predicts that Americans will take 232 million journeys of more than 100 miles this summer (4% more than last summer, 12% more than in 1991). And that’s just domestic travel.

Thus, by extension, it’s packing season. Think of Americans by the millions, standing over their suitcases as crucial seconds tick away, tossing in shoes, raincoats and phrasebooks, pausing to contemplate that bulky but comfortable sweater, stuffing it in--and then regretting the decision for the ensuing days of straining shoulders and sacroiliac.

I travel as light as I can, but with certain priorities: the extra pair of glasses, the Swiss Army knife, the flashlight, the thin wallet that hangs inside my shirt and carries my passport and some money, a minimum of clothes. Most of the time, this is a source of pride. Then again, I’m the guy who couldn’t take his wife to dinner at the Ahwahnee Hotel in Yosemite two months ago because my shoes, pants and shirts were all beneath prevailing standards. We settled for lunch the next day, but that night, I fear, shall be remembered.

With such occasions in mind, I’ve been calling veteran travelers and prying into their packing habits. Their tips ran from underwear stuffed into shoes to sink-stoppers (in case your hotel sink is lacking). If you find your favorite packing strategy unmentioned here, send it to Travel Insider: Packing, Travel Section, Los Angeles Times, Times Mirror Square, Los Angeles, CA 90053. In the meantime, may these disclosures enhance your enclosures:

William F. Buckley, author and yachtsman, says he never flies without earplugs and an altimeter, to make sure the airline is keeping the cabin pressure at the proper level.

Joe Brancatelli, executive editor of Frequent Flier magazine in New York, always wears his heaviest pair of shoes on the plane to lighten his luggage load. Like almost everyone I called, he carries his luggage whenever he can, rather than checking it through. “I can do a week in a carry-on bag,” he says. He has spent years amassing a collection of tiny toiletries to keep his kit bag small and light--and if he’s heading to a high-end hotel, he trusts that his room will have all the shampoo and soap he needs. Sartorially, the former Women’s Wear Daily reporter leans towards black, gray and white, maximizing mix-and-match possiblities.

Brancatelli is willing to buy things on the road, from AA batteries to the occasional shirt. He uses soft-sided luggage, dismissing other baggage as too heavy. On long trips to familiar destinations, Brancatelli often send clothes ahead via Federal Express and sends laundry back the same way.

Galen Rowell, a writer-photographer known for his nature scenes, always packs his film in a thick, see-through plastic bag so that he can easily remove it and have it hand-checked by airport security officers. Like most frequent travelers, he keeps his toilet kit among his carry-on baggage, in case his checked-through luggage is lost and he has to make do without it for a day or two. Among the things he stuffs into the carry-on: a change of underwear, a T-shirt, running shoes and running shorts, so that he always has the option of going for a swim or jog. Also, Rowell stretches the limits of carry-on allowances by flying with a small backpack, which he says “is not noticed the way that stuff you’re carrying in your arms would be.”

Darlene Papalini, director of guest relations for Crystal Cruises in Los Angeles, keeps up her four-times-weekly workout schedule by bringing along a pair of 2 1/2-pound handweights and a CD player, with speakers, for accompaniment. She brings several Dr. Scholl’s insoles--spongy linings that stick into shoes--and uses them most on walking trips in cobblestoned European destinations. She brings a baseball cap (useful in sun or rain), a hand-held steam iron for wrinkles, an emery board, clear nail polish (both for her nails and for halting runs in her stockings) and nail glue--”because I have never, ever been able to locate nail glue on the road.”

Jon Haggins, fashion designer, writer, corporate spokesman and tour guide in New York, always packs a bathing suit and sunblock--”you never know where you’re going to be”--and his own alarm clock, so he doesn’t have to learn how to operate the hotel clock or rely on wake-up calls. Instead of folding his clothes, he rolls them from the hem up, usually leaving the cleaners’ wrap on, to avoid wrinkles. When wrinkles do creep in, he hangs the clothes in bathroom steam.

Pat Kelly, spokeswoman for Amtrak in Washington, D.C., always packs a beach towel. “On the train, it can be used as a light blanket at night,” she explains. “And when I get to my destination, I can use it at the beach or by the pool.”

She packs her underwear, pantyhose and socks in her shoes, always remembers an inflatable neck pillow for airplanes, and in summer leans toward a mix-and-match color scheme of navy blue, white and black. On frequent vacations to France with her husband, she brings along her own French-made hair curler so that she doesn’t need to fuss with an electrical outlet converter.

Ed Perkins, editor of the Consumer Reports Travel Letter in San Francisco, has gone on many trips with no footwear other than sandals. In line with his general philosophy of packing light and simply, he brings nothing “that would devastate me if I lost it.” Even his laptop computer is an inexpensive model--a strategy he adopted after a more expensive computer was stolen from his rental car in Czechoslovakia about three years ago.

On trips to non-English-speaking countries, Perkins brings a supply of English-language paperbacks. And as he accumulates papers and other items on the road, he often discards worn old socks, underwear and shirts. To cope with accumulated paperwork that has grown too large, Perkins always brings a few waybills from an international express-mail service.

To help him sleep in the air, Perkins is never without an eyemask. He also brings a can of spray-on spot remover and a small screwdriver; more than once, he has dismantled shower heads to remove hard-water deposits and improve flow.

Priscilla Ulene, proprietor of the Traveler’s Bookcase bookshop in Los Angeles, says “the thing that pops into my head immediately is my neck pillow for the plane. I do not leave the house without it.” She is another big fan of black, gray and white clothing combinations, and of rolling clothes rather than folding them. To minimize spill potential, she packs shampoo bottles and other liquid containers in small plastic bags.

John McManus, president and founder of the Santa Barbara-based Magellan’s catalogue of “essentials for the traveler,” needs his coffee in the morning and likes it the same way every time. But unlike other travelers who bring their own sometimes-bulky coffee makers, he and his wife rely on a heating coil, two cups and Folger’s Coffee Singles, which are essentially teabags filled with instant coffee.

Not willing to take pot luck on hotel room lighting, either, McManus brings a reading light that hangs around his neck--not the kind that clips to a book, because he wants to be able to write as well as read. Other standard features in his bags: a dental emergency kit that includes a mild pain reliever and a temporary cement for loose caps or lost fillings, and an eyeglasses repair kit with screwdriver, four tiny screws and a magnifying glass. McManus also brings his own rubber sink-stopper, because many overseas hotels don’t include them and guests may otherwise have no way to hold water in the sink.

James Murphy, president of Brendan Tours in Van Nuys, offers a short, specific list. He likes to have a small flashlight along, but his top two recommendations throw shadows over that: “Something to treat diarrhea,” he says, “and something to treat an infection. I’d rather travel without shirts than do without those.”

Gilbert M. Grosvenor, president and chairman, National Geographic Society, always carries with him everything he’s going to need for the first 48 hours, along with the phone numbers of his doctor and dentist (which he once used after losing an inlay in Bali). Not surprisingly, he takes a lot of maps and usually brings a book or two on his destination’s culture and history. When he knows he’ll be spending some time in a business setting, he brings a dark summer-winter suit and rolls up his ties.

He distributes his money over at least three places--often his pocket, his wallet and his suitcase--so that he’ll be able to give a mugger something but not everything. He locks his luggage, not so much to keep things from being taken out as to keep things from being added by smugglers.

Grosvenor’s last advice: “When in doubt about the water, drink the beer.”