It is not a legal requirement, but many brides choose to change their surname to that of their partner's, or combine/hyphenate both surnames - it's simply a matter of choice.
A Certificate of Marriage is usually sufficient evidence to have personal documentation (such as your driver's license and passport) changed to your partner’s surname.
Your celebrant will register your marriage, then you can apply to the Tasmanian Registry of Births, Deaths & Marriages for the official copy.
The cost is currently $52.95 + postage (as at 16 Jan 18).
You can access the application form here: www.justice.tas.gov.au, or I can provide you with a copy of the application form.
All applications must be accompanied by proof of identity.
You cannot use your presentation Certificate of Marriage to change your surname, as it doesn't have full details of the bride and groom.