Just brainstorm ideas first. Start from your own experiences: do you find anything interesting about how Americans communicate? Do they find anything you do (the collective "you") to be unusual, even if you think it's quite normal? What differences do you find when you communicate to an American person, compared to how you communicate with a Chinese person? Write down anything that comes to mind, even if it seems silly or irrelevant. You can do the editing later. :)

I helped one student do a paper on American versus Chinese idioms. Both of which are culturally created.

Attitudes regarding gender, official status, and age can be causes of intercultural misunderstanding. Perhaps Chinese perceive Americans as too direct and blunt in their speech, and Americans may think that Chinese never say what they really mean. Body language can be confusing. Do Chinese and Americans have different ideas about personal space? Do "they" stand too close, or not close enough? Is there too much or too little physical contact? How important are facial expressions? Hand gestures? Do "they" laugh too loudly?