Native snakes are protected in NSW by the Biodiversity Conservation Act 2016, this means it is illegal to harm them without an authority or defence under the legislation.
If you find a snake you should generally not approach it, snakes are not naturally aggressive and always prefer to retreat. They will only attack humans if hurt or provoked and most bites occur when people try to kill or capture snakes. If you are interested in learning more about snakes The Australian Museum has some detailed information about identification online, or you can contact their Object and species identification team.
If you are concerned about a snake on your property would like advice or to have it removed, you can contact your nearest licensed snake catcher on the reptile handler list or a licensed animal rehabilitation group.