See this example properly formatted in the QUT Cite tool.
Standard in-text citation examples are in Getting started - In-text citation.
Author AA, Author BB. Title. In: Editor AA, editor. Title of book. Title of the Conference; Year Month Day-Day; Place of Conference. Place of publication: Publisher; Year of Publication. p. #-#.
 Lewis D. The allocative efficiency of the Australian health care system. In: Bridges J, editor. Economics and health: 2000: Proceedings of the 22nd Australian Conference of Health Economists. Australian Conference of Health Economists; 2000 Aug 17-22. Gold Coast (QLD). Kensington (NSW): School of Health Services Management, University of New South Wales; 2001. p. 213-23.
Author AA, Author BB. Title of paper. In: Editor AA, editor. Title of Conference [Internet]; Year Month Day-Day; Place of Conference. Place of publication: Publisher; Year [cited Year Month Day]; p. #-#. Available from: http://www.xxxxx.xxx.xx
 Ramirez-Nafarrate A, Gutierrez-Garcia JO. An agent-based simulation framework to analyze the prevalence of child obesity. In: Hill RR, Kuhl ME, editors. Winter Simulation Conference: Simulation: Making Decisions in a Complex World [Internet]; 2013 Dec 8-11; Washington D.C. Piscataway (NJ): IEEE Press; 2013 [cited 2015 Jun 26]; p. 2330-2339. Available from: https://dl-acm-org.ezp01.library.qut.edu.au/citation.cfm?id=2676273
Treat a conference paper in a similar way as a chapter in a book. The authors and title of the paper begin the reference, followed by the connecting phrase "In:" and information about the conference.
Put conference date in the format YEAR Mon DD-DD (e.g. 2000 Aug 17-22)