WOULDN’T IT BE NICE if there were online Packing Gadgets or iPhone Packing Apps? Type in your destination and length of stay, and up pops a list (of course, you’d need a data base listing your entire wardrobe). Now that the free checked bag is rapidly becoming A Thing of the Past, efficient stowage is more essential than ever. A few rules I’ve learned the hard way:
 
Two Colors. Start with a neutral; add one color. This guarantees that everything goes with everything else. For greater tonal variety, take scarves and earrings.
Four Shoes. Wear one pair; pack the other.Both should be good for walking (unless you are lolling, à la Maria Callas or Jackie O., on someone’s yacht). Make one pair suitable for both dress-up and daytime, like metallic flats or sandals or cool boots. Your bag should also be versatile: Longchamp Le Pliage folding totes hold lots, come in splendid colors, and aren’t too clunky at night. By the way: Always fill shoes (or any hollow space) with other stuff, like socks.
Lots of Underwear. Otherwise, you’ll spend your vacation life bent over the hotel bathroom sink and waiting for socks to dry. If you have to take less of something, make it dress-up clothes. Unless you are christening the above-mentioned yacht or opening a film festival, limit yourself to a stretchy, simple, roll-up-able black dress, or black pants/leggings and a somewhat fancy top.
Low-Bulk Layers. Global warming has made mincemeat of past weather patterns; be prepared for anything with lightweight pieces you can roll up. Layering looks quite chic and hides a multitude of body issues (try, for example, a tank under a long-sleeve tee under a long cardigan; peel off as the temperature rises). Nothing that wrinkles: If you must have shirts, Brooks Brothers’s non-iron line is truly creaseless.
One Word: Plastics. Ziploc bags—the kind that actually zip, not the kind you press together (if you don’t do it accurately and securely, all hell breaks loose)—are great for anything that might spill or that you want to protect from snagging or soiling (lingerie, pantyhose). I also use them for drawing pencils, vitamins, laundry detergent, Band-Aids…. Further spillage insurance: Put a small square of plastic wrap on open mouth of bottle and screw on top over it.