The purpose of the research methods section is to establish the credibility of your results and to enable replication.
The pattern is: I did this, because I wanted to achieve the following, as is suggested by this author.
Here is Dr Debbie Adendorff's excellent summary table of her research, as well as a couple of videos about various data collection methods.
Inductive and deductive reasoning
Survey questions
Experiments
Case Study
Grounded theory
Ethnography
Archival research
Focus groups and interviews