It can be costly to try to do these in the wrong order. Allow time to do them all.

• Products – define
• Customers – research market
• Suppliers – evaluate
• Business Plan – budget
• Business Name – choose one not similar to any existing name
• Domain Name – check availablity of appropriate name
• Register
  • Business Name with your state government: 1 day, OR:
  • Company with ASIC 1 day
  • Domain Name – register 1 day
• Bank account in the name of the business or company 1 day
• ABN from the Australian Taxation Office 4 weeks
• Credit card merchant facility from a bank 2 to 4 weeks
• Website – quotes 1 week
• Website – design 2 weeks
• Host website 1 day
• Search engine listing 10 days
• Accounting – see Small Business Accounting
• Put time into your business – see Different Results
  –

Some of the above times are concurrent, but some are not:
e.g.
You need to show ownership of a business name before you can open a bank account for it.
You need an ABN or ACN before you can get a merchant facility.
You need a business name or company registration or ABN to get a .com.au domain name.
But you can get your website developed while you are waiting for an ABN or ACN.