One of the biggest mistakes you can make, in terms of marketing, is to target too much of the market at once. The odds of dominating an entire market, for an evolving business, aren’t likely; but you can still be quite successful by targeting a narrow, niche field.
Start by researching what niche markets need your specific skills and services. One of the best ways to find out is a survey; as long as you ask the appropriate questions, that is. And keep in mind that with millions of Australians online, the internet is a pretty effective tool.