guangzou and shenzen visa

Hi, I'm holding Indonesia pasport and I wanna travel to Guangzou today, after staying 3 night, I will continue to Shenzen and bacjk to HK. My visa was expired, I need to apply new one. Please tell me what to do, because - need to go to Canton Fair in Guanzou. Hope to have early reply from you.
Thanks you, Yulia.