I want to reference the same book a few times in my assignment, how do I do this?

How you structure your in-text references in this case will depend on the referencing style you are using.

For APA, multiple references to the same source does not require a change of formatting, that is, you always need the author surname and the publication date (and a page number when quoting directly). However, there are some differences depending on the number of authors in the source (for example 3-5 authors) The source should only appear once in the reference list at the end of your document.

For Chicago, second and subsequent references to a source can be shortened.  These short form footnotes typically require only the author surname, a shortened version of the title (if more than four words), and a page number.  The Referencing Guide provides examples for first footnotes, as well as second/subsequent footnotes, for all source types.  The source should only appear once in your bibliography.  

The links below may also be of use.