Travel 101: Right Bags, Wrong Bags Want to save money on Spirit Airlines' inexhaustible parade of fees? Fly naked - since Spirit charges for any and every bag. Tip: When flying nude, always avoid hot drinks in case of turbulence. Fortunately, most airlines don't charge for carry-ons so leaving the giant Samsonite at home can save you $50. Yes, there are right bags and wrong bags. Right Bag: Carry-ons Save Money, Time Carry-ons are right because they save money and time. There's no better bliss than walking off a plane and going directly to the airport exit with no annoying 30-minute wait at the baggage carousel (that's 30 minutes if you're lucky). There are a lot of other important things you should know about bags, too; like style - and color. For more travel news and insights view Rick's blog at farecompare.com I'm no fashionista, but since as I usually manage to match my socks, I guess I'm qualified to talk about the 'look' of luggage, and this is more important than you think. Wrong Bag: Favorite Color of Thieves Guess what the favorite color of bag thieves is? Basic black. Bob Arno, author of "Travel Advisory: How to Avoid Thefts, Cons, and Street Scams While Traveling" pointed out a few years back that when cops busted a Phoenix couple for baggage theft from Sky Harbor airport, almost every one of the roughly 1,000 stolen bags found at their home was black Stealing black bags is a snap, says Arno: "If the thief is caught red-handed by the bag's owner, he only has to say 'Sorry, it looks just like mine.' And he's out of there. Scot-free. When going through security, always keep your eye on your carry-on. When picking up a checked-bag, be alert and don't forget to make it more eye-catching (and identifiable) by personalizing it with a splash of color. Multi-hued ribbons are getting kind of tired so try a big bright ID tag or wrap the handles in vivid duct tape; the "Duck" brand offers a rainbow of shades including a startling neon green. Shopping for a new bag? While black is most durable for dirt and wear, the color experts at Pantone say the hottest shade of the year is tangerine. Maybe not for everyone, though, as I notice the "orange collection" of the pricy Lipault luggage line is currently on clearance. Right Bag: Size Matters One of the most important things to keep in mind when suitcase shopping is size and weight, and this matters for all bags. Large luggage: Most airlines limit checked-bags to 50 pounds before the steep overweight fees kick in. Virgin America used to allow 70 but dropped back to 50 and Spirit allows just 40 pounds. It's worse if you fly internationally; Ryanair allows just 33 pounds during the peak summer season. Find a bag that weighs as little as possible; luggage pros suggest materials like aluminum, polycarbonate, carbon fiber and of course, lightweight fabrics. Watch the weight of those wheels, too, which can vary tremendously. Carry-bags: Airlines now post specific size limitations for hand luggage. The problem is the dimensions are all over the map, ranging from 44 to 55 inches which is the figure you get by adding the inches of a bag's height plus length and width, and you must include the wheels in your measurements. Worse, size requirements vary by aircraft and since planes are often swapped out in last-minute substitutions, you're sometimes forced to check carry-ons at the gate since overhead bins on smaller regional jets don't hold much. Warning to Spirit flyers: do not try to avoid the online or kiosk carry-on fee; if you are nabbed at the gate you'll pay $100. For other flyers, while cabin checking last-minute carry-ons is a pain (there goes all that time you thought you'd save), at least it's free. Wrong Bag: Non-Squishable One good thing about smaller duffels, gym bags and backpacks is they can be squashed to fit under the seat in front of you, a desirable trait if you're in a late boarding group and all the bin space is gone. However, I recommend this for short-hauls only, so board as early as you can. Right Bag: Proper Bin Stowage Flight attendants say, stow bags in overhead bins 'wheels out' meaning with wheels facing you, and today more bags come with a handle in the wheel area making it easier to extricate them. Don't shove your bag in side-ways; it'll eat up too much space (and someone will probably shove it back into position for you without regard to its contents). Do not expect help from a flight attendant in lifting your bag either; it is not their job (though many do assist with this chore which is why so many are injured each year). Pack only what you yourself can hoist or look to a fellow passenger for help. Wrong Bag: Filled with Valuables One last thing: You may be surprised to learn that airlines are not responsible for most valuables in checked-baggage. Many, like American Airlines, specifically ban valuables such as documents, electronics, jewelry and cash. If you don't want to lose it, do not pack it - and if you do lose it, don't expect much from your airline. Of course, if you're flying naked, no such worries.