Doh! 20 biggest travel mistakes

Collectively, we've touched down on every continent on earth and we're closing in on every country.

But we're nowhere near perfect travelers.

Every one of the travel chokes on this list comes from painful personal experience -- often multiple times repeating the same mistakes. (We're nothing if not persistent.)

1. Overpacking

At home, with your complete wardrobe available, there's no reason not to run through work, workout and working-the-clubs outfits in a single day.

But when your life is crammed into a couple bags, your fashion morality changes.

Those socks you wore on the plane should be good for another go.

The purple tee you slept in ought to be alright for a third wear.

Yesterday's undies? Well ...

According to a recent survey by Travelodge, two-thirds of travelers typically return from a trip with at least six unworn outfits.

The lesson: You don't need a new set of anything for each day of a trip. Figure on at least two wears for (almost) everything.

2. Not buying something you like as soon as you see it

You think you're gonna circle back to that shop.

You think you'll see a cheaper, better version somewhere else.

You won't.

That evocative street painting or those Metallica nesting dolls you didn't buy? Now not having them will haunt you for the rest of your life.

When you see something you like, just buy it and live without regret.

3. Not checking your phone plan before traveling abroad

What you call "international roaming" your phone carrier calls "shareholder dividend!"

A week of texts from Singapore or St. Lucia shouldn't cost more and hurt worse than open heart surgery. But it happens all the time to travelers who fail to check their phone plans before departure.

4. Trusting "near city center" descriptions

"Near city center" is like a Bible verse -- open to vast interpretation.

When you find the money you saved on your "near city center" hotel is being spent on 30-minute commutes and outrageous taxi fares, you know you've committed one of the cardinal sins of travel.

Related note: Except by purely technical definition, if you're staying near the convention center in Portland, Oregon, you're decidedly not staying "downtown" (as is popularly advertised) by any local sensibility.

5. Taking the "super" shuttle

Wait on the curb for a ride in a sweat-soaked van and risk being the last one dropped off on a nine-hotel run, all in the name of saving a few bucks?

Your time is worth more than that.

Adam Carolla brilliantly sums up this classic travel blunder in his book, "In Fifty Years We'll All Be Chicks."

"The shuttle is the worst $20 you'll ever save. It adds 90 minutes to whatever a Town Car or cab would have been. You have the unenviable choice between being dropped off last or being dropped off first and having a bunch of losers who can't afford cab fare and have no friends or loved ones with cars knowing exactly where you live."

6. Not tightening shampoo caps ... all the way

Those cute, little trial-size shampoo and conditioner bottles are really handy -- until they magically burst open in-flight, spreading a layer of glycerol soap snot all over your bag.

7. Thinking you know the perfect time to book a ticket

There's an art to reading the tea leaves of the airlines' protean pricing schemes, but there's some muddled science to it, as well.

According to Travelers Today, research conducted by Kayak found the optimal timing for a cheap-ticket purchase is 21 and 34 days before domestic and international flights, respectively.