When choosing a citation style first think about the task at hand. Here are some hints to help guide you
Writing an assignment or essay?
Before compiling your references, check your assignment guidelines or subject outline, or consult with your tutor or lecturer for the referencing style preferred by the school or department.
Writing a thesis?
Referencing styles are discipline specific. Your supervisor can advise on a recommended style.
Writing a journal article?
Each journal will specify a format for referencing in author instructions guidelines or similar. These are usually available on journal webpages.