There are many different ways to celebrate your union
I personally respect your right NOT to formalise your relationship with a valid marriage, but to acknowledge and celebrate your union. I am always privileged to be invited to create a ceremony reflecting your commitment to love for life.
Customs and conventions linked with marriage vary from country to country.
Of course you still need to set a date, select a place for your ceremony to take place, create a guest list, choose music, craft an appropriate ceremony and confirm your celebrant.
There is (for me) very little difference in the creating of a commitment ceremony to a valid marriage- except in the requirements for marriage, according to Australian law. This is still a very great occasion and your life commitment should be commemorated, in which ever way you see fitting and as a rich expression of your companionship.
If you need to mark your commitment with festivity and celebration then a Love Commitment Ceremony may be right for you both. Much will depend on my availability - please phone for a chat about what you think you might like to create, in a way that brings warmth, and sincerity to celebrate the unique couple that you are.