The following articles, arranged randomly, provide various perspectives on how to create a code of ethics primarily. And most also relate either directly or indirectly to other forms of promise (i.e., oaths, pledges, etc.). (For codes of ethics of specific companies, see the Companies' Codes categories; for corporate ethics consultants and seminars, see the Ethics consultants/seminars category.)
Authoring a Code: Observations on Process and Organization (Andrew Olson, Center for the Study of Ethics in the Professions, Illinois Institute of Technology)
(Writing a Company's Code of Ethics (W. Michael Hoffman, Perspectives, Center for the Study of Ethics in the Professions, Illinois Institute of Technology, scroll down to p.[9])
Writing a Code of Ethics (Michael Davis, Perspectives, Center for the Study of Ethics in the Professions, Illinois Institute of Technology)