When you start your visa application, it will be linked to your passport number. Your passport must remain valid for at least 6 months after you start your application. If there are any changes made to your passport, notify the Australian embassy immediately. Send your application packet with all the required documentation included. If you are missing any forms, your visa application will be at best delayed. At worst, it will be rejected.
If you have a medical condition or it is suspected you may have a medical condition, you may be asked to take a medical exam. You will receive a notice like this after you send in your application. Do not get the examination before you send in your application unless you are directed to do so in writing.
On your application, you will be required to declare you have enough funds to cover tuition, traveling expenses and living expenses for the length of your stay. If you are receiving any kind of financial aid, you will have to submit documentation showing this. Students are allowed to work while in school but only 20 hours per week.
You must be accepted to an accredited institution for full-time study. You will be asked to provide proof of this in the form of a confirmation code or an acceptance letter. As of July 1, 2007, the Australian government began to allow students to change their institutions within the first year. If you want to pursue this, be sure to follow all procedures necessary. Always keep your mailing address up to date. Your host school and the visa department will need to contact you and if they cannot, your visa will likely be revoked. Be aware of any special conditions on your visa such as the "no further stay" condition. If your visa says this, then the expiration date cannot be extended except for rare conditions (students with permission to work, government sponsorship and refugee status).
Spare yourself a lot of stress by starting the process early. Getting a visa is a bureaucratic process that will take time. Send all required forms together the first time. Make sure all your contact information is up to date. Answer messages about your application and requests for more documentation promptly.