If I want to hold my ceremony internationally, can I use a friend as my celebrant ?

Yes, as everyone else has stated as long as the legal requirements are performed by Civil Celebrant. Then your friend can do the rest.

Ut is much easier to get the legal paperwork completed in Australia first.

A ceremony that is performed at a later date after the legal ceremony has taken place is called a "Committal Ceremony"  there are plenty of good examples of committal ceremonies with templates on the internet.

If you want to get legally married overseas you can check to see if that particular country is also recognised by Australia as a legal place of marriage. A good way to check is by checking with the Australian Embassy. Also in the event of legally getting married overseas such as Bali or other countries, there may be paperwork that needs to be filled in at the Australian Embassy or Consulate of that country and a Australian Consular official will have to officiate the legal parts if two Australian citizens are wanting to "legally" get married overseas.

Otherwise if it is a non legal wedding, then anyone can officiate without using the legal wording.

Yes, for sure. your friend is a non-legal celebrant in that case also, and can absolutely do the job.

Absolutely you can have a friend complete the non legal side of your wedding.

Good Luck.

100% you're allowed to do that. You only require a celebrant for the legal paperwork :) 

Yes absoloutely! Celebrants are only needed for the legals bits - you can have your friend conduct the ceremony for you xx