Long term stay China visa

Hi all,
I and my Chinese fiancee intended to get married this year somewhere in June and ROM in Singapore. She suggested that after marriage, we will moved back to stay in Qingdao, China which she have a house there. The main reason is that she is unable to adapt to Singapore's hot weather. May I know how am I going to go about to apply for a long term stay visa in China?
Please kindly advise, thank you !