(FORTUNE Magazine) – Dear Annie: I'm a 33-year-old woman but, at five-foot-four and 114 pounds, I look about 16. As an airport planner, I have to deal with people from the Federal Aviation Administration and the Department of Defense, and they are primarily older, former military men. They usually treat me with respect once I start speaking, but their first impulse is to pat me on the head. What can I do to look older? (A few of my colleagues, both men and women, have the same problem, so we'd all appreciate any suggestions.) --Not Sweet Sixteen

Dear Not: About 1,000 people across the U.S. make a living helping business people look more professional; you can locate one through the Association of Image Consultants International at www.aici.org. Then, too, there are books--a good new one is Branding Yourself: How to Look, Sound, and Behave Your Way to Success, by Mary Spillane (Pan Books/Macmillan UK, $24.95). In the meantime, Anne Sowden, who runs a Toronto-based image consulting firm called Here's Looking at You (www.hereslookingatyou.ca), has a few ideas. First, if you're in the habit of wearing light-colored clothing, stop. "Black, navy, and charcoal create an impression of authority. No pastels!" says Sowden. "And always wear a tailored jacket." Should you pair it with a skirt or slacks? "It really doesn't matter. Wear whichever is more comfortable because if you're comfortable you'll be more confident."

Sowden says you do need some makeup--but don't overdo it: "Try a very light foundation, eyeliner, mascara, a tiny bit of blush, and a soft lip color." If you have long hair, she adds, "put it up or tie it back away from your face. Stay away from trendy hairstyles." If you don't already wear glasses, you might consider getting some, with plain lenses. "This would work especially well on those older ex-military types," Sowden says, "who were raised with all that old stuff about men not making passes at girls who wear glasses." Most important of all is body language: "Looking authoritative starts with the way you enter a room. If you hesitate, even for an instant, people pick up on that. So stand straight and stride in. Look them in the eye and shake hands firmly." But not too firmly. Some image consultants recommend practicing your grip by squeezing a tube of toothpaste, with the cap off, as if you were shaking hands with it. Your fingers should make indentations, but the toothpaste should stay in the tube. "If it squirts out all over," says Sowden, "you're grasping too hard."

Dear Annie: I'm graduating from college in June and have accepted a job as a systems analyst with a company I admire. My goal is to be a chief information officer somewhere by the time I'm 35. What do you think will be the best way to achieve that--by jumping from company to company or by staying put and working my way up in one place? --Onward and Upward

Dear Onward: You may well find that working your way up in one company will get you to that CIO slot. RHI Consulting (www.rhic.com), a high-tech staffing firm in Menlo Park, Calif., recently surveyed 1,400 CIOs nationwide and found that more than 53% of all tech management jobs are filled by insiders, while nearly a third of companies promote virtually all (90%) of their highest-ranking tech people from within. Techies as a group are notoriously restless, but try to resist the temptation to hop around too much, even after the economy perks up again.

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