How do I Actually Do This?

If you're a high school student, you will need to find a high school Student Exchange organisation. I recommend researching those registered with CASEO (Council of Australian Student Exchange Organisations) so you know you'll be in safe hands. I can also recommend the Rotary International Youth Exchange Program from personal experience. You will go to a local school and live with a host family (or several).

High school Exchange does cost a bit, and living expenses vary depending on which country you go to, so start saving as soon as you think this is something you'd like to do. Pick up a part-time job if you're old enough, and/or do odd jobs for friends and family (babysitting, car washing, lawn mowing etc).

If you're a university student, make an appointment to speak to the team in charge of global experiences. A quick search of your university website should find them.

A university Exchange program will send you to one of your university's partner unis to study regular classes that you would have to complete in your degree anyway - or you can use your electives to study something different that you may not have access to in Australia. Even if you go to a non-English speaking country, your host university will usually have English-taught courses for you to enrol in.

If you pay for uni via HECS, your Exchange studies will be paid in the same way. Additional funds will be required for travel and living expenses. You can apply for an OS-HELP loan (if you're eligible) to assist with expenses (one per semester abroad; maximum of two OS-HELP loans in your lifetime). I also recommend saving as much money as you can so you'll have enough for living expenses and extra for travel and other experiences.

If you're an adult not currently studying, you could internet search language/art/'whatever your hobby is' schools in the country you'd like to go to... OR you could consider applying for university study so you will have access to a university Exchange program. Bear in mind you will generally need to complete at least a year of study, maintaining good grades, to be eligible to apply. In my opinion - ABSOLUTELY WORTH IT. Make sure the degree you apply for has space for Exchange. Most do, but the safest would be a Bachelor of Arts or a Bachelor of Business. Whether you complete the degree on your return from overseas is up to you (but if you have just a year left, why not get that piece of paper).