Learn some basic Chinese. A lot of people（mostly students）knows pretty good English; but it never hurts to actually know how to say things like 太好啦 or 哪里可以买到包子.
Don′t go to the touristy places, because it′s not worth it and its all made to attract foreigners…so it's not China china, it's like “China made in China” sort of thing.
As far as choosing a restaurant I would suggest that when it is meal time you will see the small restaurants that are packed with people and next door a restaurant that has very few people.
