According to a recent New Yorker article, you can strike the “tall” and “healthy” part of that. We continue to be well fed, but are gradually becoming short and fat, according to the article!
I don’t know what kind of Americans you’re looking at, but in my experience (and I’ve lived in the States and the UK) Americans are a lot shorter than the average Briton. I’m 6’ and wandering around London invariably makes me feel short. Walking around any American city makes me feel pretty much average. Hell, I’m taller than most bouncers here.
They are, of course, three times wider than me
Especially on public transport, and especially in groups. It’s really obnoxious.
And please don’t complain about the “funny money.”
About learning local words - I have heard people say that in Paris or in Thailand, the locals don’t like to hear you butcher their language. I found this to be totally false. I spoke ghastly French and unintelligible Thai while in those places, but was never met with a negative response. In fact, I am baffled by stories of rude Parisians. They were extremely pleasant to us.
About the ‘no shorts’ rule - what do people in other countries wear instead? I didn’t think that shorts were exclusive to the US. And what kind of shoes do Europeans usually wear? 
Heehee
For Australia, don’t try to hide your Americanness too much. If you sew a maple leaf onto your backpack, and we find out you’re American, we’ll just think you’re weird.
Speak softly, don’t say “g’day mate” all over the place, and squint. You gotta squint. Decades of living in bright sun has made the average Aussie’s face a sea of wrinkles. To me, American skin always seems smooth and glowing like a baby’s. Be polite, but just to the extent of “please” and “thank you”. If you try the “have a nice day” stuff, it’ll backfire.
Look, nobody is going to beat you up for being American. Usually your nationality will go in your favour. American people tend to be well liked here regardless of what some folks might think about political issues. Go to a nightclub alone, and you won’t leave alone, put it that way. On the other hand, you’ll be in the spotlight, and subject to more scrutiny than a local would be if you fuck up. But that applies to any foreigner anywhere in the world, unfair as it is.
Generally, just be yourself. Leave the Hawaiian shirts at home though.
It’s something that us Brits find embarassing - as soon as the sun shines, middle aged men appear in shorts they should NOT be wearing, probably because they bought them fifteen years ago. As I posted earlier, light trousers are actually more comfortable in hot weather, they keep the midday sun off your skin, and you can carry on through the evening without running back to the hotel to change into something warmer.
Italian men wear proper leather shoes without socks - but that’s helped by being able to buy decent leather shoes for a reasonable price in Italy. With the aforementioned trousers, I’d either have semi-respectable sandels, or shoes and socks.
I’ve only visited Europe in the winter, when there are obviously no shorts worn, but I have lived and traveled in parts of Asia for a decent length of time, so here are my observations of Asia.
The only people in Japan (that I’ve seen) who wear shorts are small children and foreigners. Japanese people, and Asians in general, dress more conservatively. I went to Kanazawa and visited a famous, multi-acre garden under the 90+ degree blazing sun of August. The Japanese tourists were wearing jeans, casual khaki pants, dressier cotton pants, or skirts that generally ended no higher than an inch or two above the knee (with stockings sometimes). No bare shoulders, either.
I don’t see people wearing shorts in my area of Western Japan. Even in the horridly humid summer weather, they wear long pants, capris, or (usually) modest skirts. The only shorts I see on anyone over age 10 are long, baggy shorts that go below the knee, worn by teenage boys.
When I ride my bicycle around town wearing shorts (that go to mid-thigh), peoples heads swivel as I go by.
In SE Asia, it’s even more conservative. People go swimming in the ocean in all their clothes, even!
This wouldn’t have anything to do with, um, lack of pigment, would it? 
But when the Brits, and most other European nations, go on holidays they wear shorts, or the vast majority do, so why shouldnt the American tourists wear shorts if they want?
In Ireland I dont understand why so many Americans wear shorts when its not warm, but hey if theyre comfortable then leave them be, theyre not the only ones who do it… the Spanish, and the Germans (especially the German tourists, and theyre even shorter then american shorts!) always wear shorts.
If you dont want to be seen as a stereotypical american tourist, like the others have said, just be polite, respect local customs, if appropriate learn the lingo, dont get in the way, and dont insist on screaming at each other when your talking.
But thats true for all tourists not just american ones.
One of the most important phrases to learn is whatever the general interjection is for “you’re welcome”, such as “prego” in Italian. You will use it many many times, and because it’s at the end of the interaction, it’s a nice way to conclude.
One of the most important phrases to learn is whatever the general interjection is for “you’re welcome”, such as “prego” in Italian. You will use it many many times, and because it’s at the end of the interaction, it’s a nice way to conclude.
Okay. How do I say “You’re welcome” in French?
“De rien”. Literally “of nothing”, but it’s the expression. (Hell, in Italian, “Prego” means just about everything polite…)
On the other stuff:
Don’t wear a Canadian flag. As long as you are not rude or obnoxious, nobody will be upset that you’re an American. In fact, being a well-behaved tourist helps fight the stereotype of the “ugly American”. Unless you are ashamed of your country, don’t pretend you’re from another one. Plus you will look like a schmuck when you get into a conversation with somebody and reveal you’re an American. I don’t know what “difficulties” clayton_e has avoided by wearing a Canadian flag, but I’d sure be interested to hear.
If by “typical” American tourist, you mean “stereotypical”, some of the previous suggestions are good. Make an effort to learn and use the language, don’t be loud or rude (as you have said you are anyway), don’t complain about how things aren’t the way you’re used to them (though I always complain, privately to my travel companions of course, about the toilets outside the US).
Chances are you will be picked out as an American anyway, but unless you are planning to change your wardrobe, accent, or skin color just to go on vacation, don’t worry about that. People don’t dislike Americans (except maybe in France, but I can speak French fluently and with a French accent, so I can’t know for sure), and there are certainly countries with ruder tourists than the US, so as long as you are respectful, people will be OK with you. In any case, Americans are not that hard to pick out. I just spent a week in Italy and you could just about always tell who the Americans were. After a few days I could also tell some other nationalities, like French, Germans, Brits, etc. So it is sort of a lost cause to hide your nationality unless you want to pretend you are Canadian. You are much better off trying to avoid fitting the stereotype than avoid fitting the type.
Thanks, Fang.
I hope that I will be pronouncing, “De rien” correctly!
You are an American tourist so live with it. If you aren’t loud or obnoxious or any of the other traits that offend, why are you trying to hide that fact? Would it be better if they thought you were a French tourist? WTF? or rather FU!
I truly can’t imagine trying to pass myself off as Canadian. Never understood that “strategy.” To me, it’s more desirable to be a nice American than a fake Canadian.
We’ve traveled a fair bit in Europe, our main thing to do is learn a bit of the local language/customs/history. We dress neutrally, but as soon as we speak it’s going to be obvious where we are from. We just do our best to go along and get along.
kniz
Just wanted to add, I quoted you because I agreed with you. 
Pants, skirts, djelabbahs…depends…
Over here, someone would wear a short for sports, or at the beach, for instance. Not in a city’s streets.
Someone nailed it above, don’t be a jerk and remember you are representing your country on a personal level, so be an ambassador.
Why the hell anyone would want to sew on a canadian flag or maple leaf (unless they are really into them for some reason as opposed to trying to look Canadian)? Soon as you’re pegged as a US citizen, people will think you are wierd or a big dickhead.
I’m an american. I am ashamed and embarrassed at times by what my country and some of it’s citizens do, but I don’t shrink away from it. I sure as hell don’t try to hide by claiming to be Canadian (nothing against Canada).
I’ve been fortunate enough to have traveled extensively and can say that some really good advice has been given. My only advice would be to listen to it.
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However, I do have a question. I am going to Morocco in the fall and will be in the cities as well as some rural areas. I know to dress conservatively and I could “pass” as I am dark haired, dark eyed and have light olive skin. Would a head covering be necessary? Or disrespectful? A hijab, scarf or don’t even bother?
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