Non-verbal communication and language learning.
http://thelinguist.blogs.com/how_to_learn_english_and/
The above essay is very interesting. I agree with Steve on the point cited below.
“If you try to deliberately imitate an Italian gesticulating,for example, you will just look foolish. The same would be true of a Japanese person who tried to behave like an American, … without first having naturally acquired the sense of how these non-verbal forms of communication work.”
We do not shake hands with other people very often in Japan; we usually bow each other when we are supposed to shake hands. The problem is I sometimes shake hands bowing. I cannot stop myself bowing when I am shaking hands with other people. I think It is like speaking two languages at the same time.
An interesting insight, Yutaka. Thanks for sharing.
My goal is to be able to speak in English like a native speaker of English without behaving like , for example, an American. Do you think it is possible?
haha this thread is a little misguided I think. No american will ever say “Wow you have grasped our american culture, congratulations!” since the US is a giant mix of cultures, and of peoples “americanized” to different extents.
Even if you do not try to imitate a foreign gesticulating, your way of gesticulating is going to be influenced gradually by learning a foreign language. I sometimes feel that mixed gesticulating is funny and strange like speaking different languages simultaneously.
When I am writing, I do not worry about my mixed gesticulating. 
When you are writing, you cannot gesticulate with your pen. But you can use punctuations, such as periods, commas, colons, semicolons, and dashes. You can use small letters and capital letters in writing. It goes without saying that they are very useful when you are writing.
As to speaking like a native, I still haven’t managed it… As to behaving like one, that’s not too hard these days in the UK, there a no rules anymore.
While you cannot gesticulate with your pen, you can bring your mood across not only in the the way you use punctuation or the choice of your words, but your posture can influence your writing style (both physical and mental) and subsequently your communication.
I am now at my desk in pajamas, a cat on my lap. Can you notice this?
Honest man that I am, I have to confess that I told a lie. No cat on my lap. She is now downstairs.
Had I seen a sample of your handwriting ‘with cat on lap’ and then one without cat, would I have seen a difference?
Off topic: How does the cat get on with the ducks?
Hey Yutaka, The main thing is to behave like yourself in the United States. I am an Irish American married to an Italian American. My family doesn’t use many gestures when we speak, but my wife’s family, being Italian, uses their hands a lot. You will find Asian Americans to be very formal and reserved like they are in their native countries. Just be who you are.
It is interesting! I am Russian, but my gestures like Italian. My friends so consider.
YutakaM, hi!!!
About the possibility to speak English like a native speaker. I think it depends on personal predisposition to it. May be it is memory of generation. Probably, you observed, some things are very easy and others more hard or impossible for you. For example, my pronunciation in English is very bad, it is difficult for me although English takes much time. And one week in Italy and I get fine estimation of my pronunciation, which is like a native.
oh, when it comes to “speaking” like a native yeah that’s hard. I’ve spoken english fluently since like 1st or 2nd grade I think but I’ve always had a strong ukrainian accent, even though it takes zero effort for me to think/write/watch tv/etc in english and indeed I often think in english.