Thank you for the opportunity to help you with your question!
There are paradigms (such as action research), methodologies (soft
systems analysis, for example), and methods. You will change
your mind during the course of the study about methods, so you need
not concern yourself too much about them now. You may even
change the methodology you use; but it doesn’t hurt to begin by
choosing one as the possible vehicle for your study.There are
advantages in following a published approach. In particular it
can be simpler to use a process described by an author who has
sufficiently explained and justified it. In your eventual
thesis it is then someone else who is providing much of the
justification for what you do. This is less risky than having
to provide it yourself.By the way, I do
not think you should accept anyone else’s arguments
uncritically. Satisfy yourself that the argument is well
made. Better still, suggest some improvements.
Please let me know if you need any clarification. I'm always happy to answer your questions.