Abstract: Language variation studies, initiated by William Labov, the great American sociolinguist, are distinguished from the other studies for its focus on the varieties of language forms and “the system of orderly heterogeneity”.There are two major paradigms in variation studies: quantitative paradigm and qualitative paradigm, though they are usually used together in researches to avoid their respective shortcomings.Variation studies are special for its strict methodology, and collecting the lively daily used language data is one of the salient features.This paper discusses what concrete methods are used in collecting data and analyzing data and how the methods will be applied in foreign language teaching.