The Central Coast has been a single council area since 12 May 2016, when Gosford City and Wyong Shire councils merged to form Central Coast Council. The NSW Government's Central Coast Regional Plan 2041 names Gosford as the regional capital and Tuggerah as a regional city, and expects a population of around 347,500 in 2021 to pass 404,250 by 2041. Customers still describe where they live by town, though: the Woy Woy Peninsula, Terrigal, Erina, The Entrance, Tuggerah, Wyong, Budgewoi. Those are the names to use on your site.
Licensing works the same as anywhere else in the state. Your contractor licence comes through Building Commission NSW, and specialist trades (electrical wiring, plumbing, drainage, gasfitting, and air conditioning and refrigeration) need one for a job of any size. The NSW Government's advertising guidance requires the licensee's name and licence number in all advertising, online included; if you trade under a registered business name, that can be used instead of your own. Customers can check a licence's status, categories and expiry date on the Verify licence site.
Central Coast Council's Greater Warnervale Structure Plan, since endorsed by the NSW Department of Planning, Housing and Infrastructure, sets a framework for that area to grow from about 20,000 people to about 57,000 over 20 years, with sporting and community facility upgrades proposed at Warnervale, Wadalba and Woongarrah. If those estates are where your work is, they deserve a mention by name rather than sitting under a general "Central Coast" heading.
Bush fire rules shape some jobs too. In NSW, land is bush fire prone if it's designated on a map certified by the Commissioner of the NSW Rural Fire Service, and a property can be checked with the RFS's online tool or on the NSW Planning Portal. Development on mapped land has to meet Planning for Bush Fire Protection, currently the 2019 edition, which the RFS says is going through its five-yearly review. A trade that regularly works on those blocks can say so, without making promises about any particular property.
We're an Adelaide team and work with Central Coast tradies by phone and email. One of our clients, Phoenix Housekeeping, covers the Central Coast along with Lake Macquarie and Cessnock, and its site has suburb pages across that whole area. For most coast trades we'd suggest a smaller version of the same idea: your base, the towns you cover from south to north, and a note if you also cross into Lake Macquarie or the northern edge of Sydney.