The subclass 888 is a permanent visa that would allow you to stay in Australia indefinitely. This also gives you access to unrestricted rights to work and study in Australia, and allows you to apply for a citizenship in Australia once you are considered eligible.
Since the temporary subclass 188 visa is the first stage to a permanent visa, you must first meet the requirements for this subclass. Once you have met the requirements for the 188 visa, you should be nominated by an Australia State, Territory or by Austrade and hold a realistic commitment to maintaining business/investment activities in Australia.
If you are a holder of the subclass 444 or the special category, then you may also apply for the subclass 888. Your immigration agent in Sydney will advise you of your options once you have given them all the necessary details.