First of all, just in case you are asking What are nameservers? Now that is out of the way.
To make DNS changes at Melbourneit.com.au, log in to your account and follow this guide.
1. Select ‘Make Changes’ and enter your domain name (without the www) and registry key, then click ‘Enter Management’.
2. Select ‘Delegation Details’, do not use Name Server Functions.
3. Enter the new name servers in the Primary and Secondary fields.
4. Click ‘Submit Delegation’ to submit the changes.
Note: You need to enter a minimum of 2 nameservers.
Warning: Do not enter your IP address; this will cause problems.
Remember, it can take up to 72 hours for the changes to take effect.