There are two different ways that you can qualify for your teaching methods, either through:
studying a Bachelor in Education that integrates coursework for your teaching method(s), or
gaining a Master of Teaching and choosing teaching methods that align with your previous studies.
Often, upon application, you will need to select which teaching methods you are interested in pursuing.
Each tertiary institution then has subject content requirements which applicants must satisfy in order to be able to teach these different subjects. These requirements may vary depending on if the subject will be your major or additional/minor teaching
Not every tertiary provider offers every teaching method, so make sure to do your research to find out if your preferred institution offers the method you would like to teach.
Each provider will have different requirements, and you can contact them directly or look on their website for more information. As an example, this brochure from the University of New South Wales outlines the requirements of prior tertiary learning in order to undertake different teaching specialisations. Remember:
Each university is different and so ensure to check with the university
you are intending to apply with.