Check out these comprehensive guides on the Chicago/Turabian Style:
About:
In CMOS, footnotes are used to point a reader to the specific source used for a quotation or idea within a paper. After the first footnote, or if the source is cited in the Bibliography, a condensed footnote should be used. This includes the author, the title of the source, and the page number(s) that's being cited. If the writer is citing the same source consecutively, the source can be shortened down to author, page number.
Placement:
"Add a superscripted note reference number immediately following the quotation or idea you wish to attribute (typically at the end of a sentence). Footnotes should be numbered consecutively though your paper (not restarting from 1 on each page)" (Noodletools). To add the footnotes on a Google Doc, click the "Insert" tab and select "Footnote."
Footnotes on Noodletools:
Noodletools provides the user with footnotes for their sources IF the citation has been exported to Noodletools directly from the database.
Click on the three dots next to the source and select Footnote format:
Next, adjust the footnotes with the correct page number and copy the appropriate footnote depending on your need (full OR shortened note) :
Date of Publication:
Author: