To get Married in Australia you must:

not be married to someone else
not be marrying a parent, grandparent, child, grandchild or sibling (brother or sister)
be at least 18 years of age, unless a person aged between 16 and 18 years of age has court approval to marry
understand what marriage means and freely consent to marrying
at least 1 calendar month before the date you plan to marry (but not more than 18 months), lodge a Notice of Intended Marriage with an authorised celebrant.
include words required by law in the ceremony and be married by a registered celebrant.
provide an original birth certificate, photo ID or passport in English, or an official translation of the document from another language.
You do not need to be an Australian Citizen to Marry in Australia

If either person has been previously married you must provide:

Foreign language certificates must be officially translated into English.

(Excerpt from the NSW Government Website)