If your travels ever take you to the United Kingdom, you may want to avoid sticking your index and middle fingers in the air with your palm facing toward you.

“It’s the equivalent of giving someone the finger,” explains Heather Dickson, assistant publisher at Lonely Planet as well as a Brit. “Don't order two beers in this fashion in UK bars,” she adds. “Doing it palm facing out is okay [as if you were flashing someone] the peace sign."

Speaking of okay, in Brazil it’s not okay to make the “OK” sign with your fingers as “it’s extremely vulgar and means you’re talking about fornication,” says frequent overseas traveler Philip Guarino, who advises business travelers about cultural behavior. In lieu of the okay sign, he says, you might want to give Brazilians a thumbs up. However, if you do that while while visiting Iran, it’s the same as flipping the bird.

Can’t we all just get along?

Even if you do bone up on your destination’s customs before you go, it can be all too easy to slip up, in which case it also helps to know where the locals are the most forgiving. VirtualTourist.com member Suvanki isn’t a big thumbs up flasher so she wasn’t too worried about slipping up on her trip to Iran, yet “within a few hours of arriving, to affirm a ‘yes’ to a question, there I was with my thumb up, which I quickly tried to cover,” Suvanki recalls. “My guide gave a smile of understanding. Then I did it again, and yet again during my trip. Luckily, this was recognized for what it was, and not meant as an insult."

For other ways you may be ticking the locals off, read on.

Put your right hand out.

When in Japan, “don't smile, and always cover your mouth when you laugh,” advises Michael Fazio. “If you don't, especially in business, they will assume you are either being patronizing or you are not highly intelligent,” he says. Also while in Japan, says Marian Goldberg, “bowing should become a habit, for greeting people, thanking people, and saying good-bye. When you are leaving always wave, and keep waving until you don’t see your host anymore. They will do the same.”

If like me you’re left-handed, you may have some adjusting to do in Morocco, Nepal, India, Turkey, and Africa, where the left hand is traditionally used for the toilet and the right for eating, according to several Lonely Planet editors. Virtualtourist member Odinnthor concurs, based on his travels to Ghana, that “when interacting with the local people, be conscious of using only your right hand. Hand over money with your right hand, eat only with your right hand, and if you forget and use your left in an interaction, apologize and smile,” adding that “although conditions in Ghana have greatly improved regarding personal sanitation, the custom will remain for a long time.”

While in Thailand, “don't be alarmed if a local unabashedly picks their nose while talking to you,” says Lonely Planet warehouse manager Scott Stampfli, who’s married to someone from Thailand. “It's considered a natural act of good hygiene.”

Watch how you sit.

While in the Egyptian Consulate’s office three years ago, VirtualTourist member Zanzooni recalls she “was sitting with her “right leg over my left, with the bottom of my shoe facing outwards. This rude burly security guard came by and smacked the bottom of my foot and shoved it down. My friend told me that it's considered rude and disrespectful to have the bottom of your foot showing towards someone's face. I had no clue whatsoever."

During a train ride from London to Epsom earlier this year, Maiden Voyage blogger Emily Starbuck Gerson was dressed down by an Englishman sitting across from her because she rested her feet on the empty seat in front of her. She apologized and removed her feet and noticed later in the train station a sign that discouraged the practice. She confirmed later on with a less-hostile Brit that feet on seats is a no-no.  “Now I know to be more respectful of public property when I'm traveling, even if my shoes are clean,” Gerson says.

Watch what you say.

When in Europe, lower your voice, Guarino says, as “Europeans constantly complain about Americans’ loud behavior in restaurants and public places - it’s very tacky. Most Americans don’t even realize they are doing it. Rule of thumb [is] listen to the volume of people around you and follow it.”

Shortly after starting his job in a London outdoor sports store, Brandon Wick advised a British customer to purchase a fanny pack for his day hike, at which point Wick says the customer “stared at me with an incredulous look for a few awkward seconds before explaining to me that [fanny packs] were called ‘bum bags’ in the UK,” since for the British, the word “fanny” is synonymous with “vulva.”

Watch how you eat and drink.

In Vietnam, “don't stick [your] chopsticks into rice when you're done. Instead, rest them across the top of the bowl. Otherwise it reminds locals of tools used to clean ash out of funeral urns,” says Lonely Planet U.S. travel editor Robert Reid.

While dining in China, Fazio says not to “finish everything on your plate [as] it gives the message that you're not satisfied and want more. And when in China, if you find yourself at a round banquet table in a seat facing the door, as Judy Woodward Bates did, know that it’s a seat of honor. As the special guest, Bates was served an elaborate chicken dish on top of which was “a complete chicken head, comb, beak and all.” Speaking through a translator, Bates says she “bowed deeply and said that I wasn't worthy of such an honor and that it would mean a great deal to me if I could honor [the elderly Chinese man also at the table] by allowing him to have the chicken head.” This was deemed acceptable and she watched as the man “lifted [the chicken head] onto his plate with his chopsticks and then with a loud crunching noise I still recall all too vividly, cracked the skull and began devouring the chicken brains.”

Coffee-drinking tourists in Italy should note that a practice “that drives Italians crazy and makes them totally contemptuous of Americans [is] ordering a cappuccino after late morning,” says Emmy Award-winning journalist Elyse Weiner. “In Italy, cappuccinos are never consumed past breakfast time” and further, a latte simply means ‘milk’ in Italy so you will get quizzical looks if you [order one] at a bar.” Grocers in Italy also hate it when you touch their produce, Fazio says. “Ask the grocer to select your items and take whatever you are given.”

Don’t bring insulting flowers anymore.

“My French hosts looked a bit taken aback when I presented them with a wrapped bouquet of six red carnations,” says Trip Chicks tour guide Ann Lombardi. “Red, as I later found out, apparently implies romance. In addition, French custom is to give an odd number of flowers and to unwrap them in front of the recipient before handing them over as a gift,” she says. With that in mind she shied away from red flowers while in Korea and “took my Korean friends a bouquet of white lilies, only to realize after the fact that white is the color of death. Major embarrassment for me,” she says.

Know when to cover up.

While planning a motorcycle trip through Turkey, Syria and Jordan, Stephanie Hackney says she “worked hard to educate myself on Islam and the rules for women and their interactions,” yet she found that rules varied not only from country to country but sometimes within each country.  “For instance, when entering a mosque in Istanbul, I was not required to wear a head scarf. In other parts of the country, where the culture is much more conservative, it was a given that I would wear one. And, it was a requirement in every instance in Syria. In Jordan, and especially in the most conservative towns I visited, all women are covered, if not from head to toe then at least from the neck up.”

Despite being totally covered while sitting in an Armenian church in Syria, Hackney says she was called out by an elderly woman for exposing too much ankle. “Who knew that it was inappropriate for that thin sliver of skin between the top of my sock and the bottom of my pant leg to show? Apparently, she did! And, thanks to her, I now do too.”

Men are accountable in places of worship, too. Waiting in line at the Meenakshi Temple in India, VirtualTourist.com general manager Giampiero Ambrosi encountered hostility from other temple visitors because he was wearing shorts. Once the “no shorts” policy was explained to him, he bought and wore what he refers to as a “man sarong,” which enabled him to enter the temple while respecting the spirit of the policy.