For obtaining a Partner visa, you must be married to or in a de facto relationship with one of the following:
Australian citizen
Australian permanent resident
Eligible New Zealand citizen
You should first apply for a temporary Partner visa, and then subsequently for a permanent Partner visa.
Current updated information on Partner visa requirements and procedures can be found at
https://www.border.gov.au/Trav/Visa-1/801-
or https://www.border.gov.au/Trav/Visa-1/309-