While this past summer's alleged aviation terror plot in Britain caused plenty of confusion among business travelers, the good news is that many of the anti-terror security screening rules that followed have been relaxed. But if you're still puzzled as to what may be carried in hand baggage or how long you'll be standing in line, read on for 10 up-to-date nuggets of airline travel advice that'll help make your trip a smooth one.

1. If you can, take it with you. More airlines are lowering the weight limit on checked baggage (the maximum used to be 100 pounds per bag; now it's 50), which translates to extra delays and overage charges for business travelers who don't know the rules. "Weigh your luggage ahead of time, and if necessary, put the contents in two bags weighing 49 pounds each," advises Chris McGinnis, editor of Expedia Travel Trendwatch. Obviously, carry-ons are still your best bet. "Baggage claim can hold you up at least an hour, plus the extra wait time will cost you if you've pre-arranged a for-hire vehicle," adds McGinnis. For more information about individual airline luggage restrictions and limits, visit http://www.freetraveltips.com/Links/Links_airline_links.htm.

2. Update your IDs. Due to stricter national security rules effective January 8, 2007, travelers to and from the Caribbean, Bermuda, Panama, Mexico and Canada must furnish a passport to re-enter the United States--a valid driver's license and birth certificate will no longer suffice. To obtain a passport, you can speed through anticipated red tape by downloading and mailing in the required paperwork found at the State Department's website. http://travel.state.gov. To renew one in a hurry, says Travelocity editor, Jennifer Catto, "You can Fed Ex or overnight it to your local passport office for an additional $70 fee." Also, depending on where you're headed, you may need a business visa. Visit http://travel.state.gov/foreignentryreqs.html to determine which credentials you'll need to have before booking your trip.

3. Minimize your personal grooming routine. The Transportation Security Administration (TSA) has eased its recent ban on liquids, aerosols and gels. As long as you transport such substances in containers that are sized three ounces or less, that fit comfortably in one (and only one!) quart-sized clear plastic, Ziploc bag, you're in the clear. If you're a frequent business traveler, items you typically pack in your toiletry kit, such as shampoo, shaving lotion and mouthwash, probably fit this bill already. It's also been reported that you can't bring duplicates of your three-ounce toiletries. For instance, if you bring three small tubes of toothpaste in the plastic bag, airport security will confiscate two of them. One airport-hassle-free option is to leave your toiletry kit at home and plan on buying essentials when you arrive at your destination.

4. Stay footloose and fancy-free. Since you'll be required to remove your shoes at nearly every airport security checkpoint, you'll save time by donning a pair of slip-ons, rather than shoes with buckles or laces. As for fashion accessories such as belts, watches and jewelry, double-check your wardrobe and pockets before passing through metal detectors. The moment you trigger an alarm, airport screeners will automatically escort you to a secondary inspection, which entails a thorough body frisking and carry-on luggage check.

5. Don't forget your doctor's note. You're still permitted to bring all prescription and over-the-counter medications, baby formula and even injectable syringes along, provided there's an authentic professional prescription label, either on the containers or within a supporting, written document. But be forewarned: The name on your drug containers must exactly match that on your ID and ticket. "If you're female and recently changed your name due to marriage, bring along your marriage certificate," recommends Catto.

6. Drink up, lawfully. You can still bring a cup of coffee, juice or a water bottle on board an aircraft, but it must be purchased in the secure boarding area, past the airline's security checkpoint. Beverages obtained outside this boundary won't be allowed on board and must be consumed before boarding. If you're on a long, overseas flight, such as New York City to Hong Kong, the most practical way to stock up on power performance-type drinks is to take along mix-it-yourself energy packets.

7. Get wired for the skyways. While there haven't been any changes to the list of permitted and prohibited carry-on items issued by the TSA, recent incidents involving spontaneously combustible batteries found in Dell and Apple laptops have sparked some concern. "Korean and Virgin Atlantic airlines initially banned their usage, but the defective ones are out of circulation now," reports McGinnis. Mobile phones are the only tech devices off limits while in flight. BlackBerries, MP3 players, iPods and laptops are all allowed, except for the first 15 minutes of flight time.

8. Remember: Timing is everything. While most airlines continue to recommend arriving at least two hours before departure for both domestic and international flights, it really depends on which airport you use. For instance, as winter weather approaches in the Northeast, de-icing work could tack on an additional 30 to 60 minutes to your takeoff time. A new TSA website tool can help you calculate just how far in advance you'll need to arrive at the airport for your specific travel date, airline and flight time. "Be especially careful when you're traveling around the holidays," Catto advises. "If you're flying out of a major city, try to depart from one of the area's alternate airports." Alternate airports in major cities include Newark or LaGuardia if you're leaving out of New York City, Ronald Reagan National if you're leaving out of Washington, DC and Ontario International, John Wayne or Long Beach if you're leaving out of Los Angeles.

9. Devise a Plan B. When traveling out of the country, leave behind a copy of your itinerary, passport, credit and health insurance cards with family, friends or co-workers so you can be accounted for in an overseas emergency. "If you're planning to stay in a country with an unstable political climate, Catto advises registering with the U.S. State Department or the U.S. embassy or consulate in that country. "Registration makes your presence and whereabouts known and can be crucial if evacuation becomes necessary," Catto says. For up-to-the-minute travel warnings and public announcements, contact the Office of Overseas Citizens Services, American Citizens Services and Crisis Management, Bureau of Consular Affairs at (202) 647-5225 or at http://travel.state.gov.

10. Take control of your (air travel) destiny. Given the rise in terror threats, air carriers are constantly making adjustments to existing ticketing policies in order to accommodate passengers who want to adjust their plans. Therefore, says McGinnis, "Booking online is the greatest thing to happen to travel since the jet engine. It's empowering to pick the seat you want to sit in, compare hotels side by side, or decide whether to make a stopover or not. Whether you're running late or have a change of plans, you can quickly cancel or void your travel transaction online, without having to contact an agent by phone."

Erika Welz Prafder is a New York-based freelance writer and the author of Keep Your Paycheck, Live Your Passion: How to Fulfill Your Dream Without Having to Quit Your Day Job (Adams Media). Regarded as an expert on career and small business topics, she is a popular talk show guest on such TV and radio programs as Fortune Small Business, The Dolans and Fox & Friends.