Different citation formats are used by different academic disciplines. Professors will often require a particular format, but if they have no preference these guidelines may be helpful:
https://library.ucmerced.edu/research/students/citing-sources
ALWAYS ask your instructor if she or he prefers or requires a particular citation format for any written project produced at UC Merced. Many instructors will prefer that you use the citation format most commonly used in a particular discipline. Others may not have a preference. But all of them will want you to stick to a single citation format once you've decided which you'll use.
From time to time, the Library offers workshops on citation formatting and bibliographic citation managers. Some of these workshops are recorded and available from the Library's website. Here's a list of workshop recordings:
Choosing a Citation Management Tool by Elizabeth McMunn-Tetangco
Citing Sources by Sara Davidson Squibb