I now own three chinese hamsters, two males and one female, and like to think I know a fair bit about them. For starters, they need as much space as you can afford to give them, and preferably deep cages and lots of substrate because they love to dig.
They are also prone to diabetes just like dward hamsters, and so their diet should include as little sugar as possible. Treats without sugar are much better for their health too.
Wherever possible chinese hamsters should live alone. Females inparticular tend to fight to the death on many occasions, but males are slightly more tolerant of each other (like mine, but I did not buy them from a pet shop together - see this post for more info).
The best thing about chinese hamsters is they are so friendly. Pea often clings to my finger or darts in and out of my clothing, sometimes even falling asleep in my sleeve or pocket. They are lovely little things and it is a shame they can be so unpopular because of how they look.