How to access banned sites: Facebook, YouTube, in China?

I've recently came to China, where there is no way to access Facebook, YouTube, and or Twitter in the country because they all have been banned. What I wanna ask is: Are there any special tools or browsers that could possibly help me to break the ban and start accessing them again? Where can I find and download it? Before, I had found some YouTube & Twitter users from China, so I guess there must be some way that was enabling them. I do really need yr help, and please leave some answers and or suggestions below this. Ty!