To use a footnote, put a superscript number into your text and then the footnote at the bottom of the page.
Format:
Author, Title (edition, Publisher | year) page number.
Example:
12 Jonathan Herring, Medical Law and Ethics (4th edn, Oxford University Press 2012) 146.
The only difference is the author is now listed surname first and you do not include page numbers.
Format:
Author, Title (edition, Publisher | year)
Example:
Herring J, Criminal Law (12th edn, Red Globe Press 2021)
Jones G, Goff and Jones: The Law of Restitution (1st supp, 7th edn, Sweet & Maxwell 2009)