I'm applying for the partner visa (currently a fiancee in Australia, but will be married before application is made.)
Firstly, there's two visas where you can be a fiancee.
Off-shore only is the Prospective Marriage Visa, which basically allows you to enter
Australia on the basis that you are going to marry an Australia. Then you proceed to apply for the Partner Visa.
Off-shore or on-shore is the Partner Visa. You are either de facto or married to your partner/ sponsor.
There's tons of PDF files to download and read over with check lists etc. You need to get relevant police checks done, which you can read more about in the information PDFs. You need to have a medical exam done by a certain institution if you are on-shore, but if you are off-shore it's only by request of the immigration dept, as far as I understand. You need a birth certificate with both your parents names, or a copy of your birth registration, which you can request from the appropriate provincial institution. The rest is filling out forms, making statements, etc.
If you are de facto, or engaged, you need to prove you've been together for 12 months prior to your application. You need to prove that you have been together for 12 months with bank accounts, finances, rental leases etc. You also need statements by Australia citizens that can back up your relationship.
If you are married, you need to supply a marriage certificate. You do not need to provide evidence of a 12 months relationship, but you do need to prove that you have a mutually-exclusive relationship and that you did not get married for citizenship gain.
Your partner is your sponsor, so they will ask for proof of employment, but that info is all on the PDF's.
If you need a good PDF reader, try foxit reader, which is a free download, and lets you read and fill out PDF forms.
The list that I have is this:
Visa 820-801 Partner Visa check list
Form 47sp (immigrating partner)
Form 40sp (sponsor partner)
Character Penal info
Form 888 Statutory declaration by supporting witness relating to partner visa. (Basically your people support that you are in a relationship.)
1127 Partner Migration PDF booklet.
And I have a copy of form 80, which is something that is not required but may be requested in further support of your character.