I presume that you and the person in Australia already have Facebook accounts, for without one you cannot post photos on Facebook.
Go to your Facebook timeline and just underneath the section with People You May Know you will see a box with the headings Status, Photo/Video and Life Event.
Click on Photo/video and then on Upload Photos/Videos.
Select the photo that you want to share and add any comments.
Click on Post in the right hand corner of the box and wait for the photos to appear on your timeline.
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