Although it may seem tedious, citation format is important because it will help you put together papers that reflect the standards and practices of the academic discipline in which you are writing.
But the most important thing to remember is your citations must be useful. They must contain the information someone else will need to find the sources you've used. Your citations should map out your research process, and allow someone else to follow in your footsteps.
Citations also help to avoid plagiarism. Remember to:
Whichever style you use, it is important to note the information you need to create a citation.
For a magazine, newspaper or journal you will need: author, publication year, periodical title, article title, volume & issue, page numbers, and a DOI or stable URL, if accessed online.
For a book you will need: author, publication year, title of work, location & name of publisher.
For websites and other types of material (movies, music, videos), check an online or print style guide.