Unlike the star known as Polaris in the Northern Hemisphere, there is no polar star indicating south in the night sky of the Southern Hemisphere. However, there is a useful celestial marker known as Crux, or the Southern Cross. It is a constellation that roughly forms the shape of a Christian cross, and whose "vertical piece," so to speak, always points in the general direction of south when followed from its "top" to its "bottom." There is a "False Cross" constellation in the Southern Hemisphere as well, so knowing how to locate the correct one is vital for purposes of navigation.
Face to the south in an area with a clear line of sight and an absence of light pollution. If you don't know which direction you are facing, slowly scan the horizon in a circle from your position in the winter, or scan points high in the sky in the summer.
Search for a group of four bright stars and one faint star that form the shape of a kite. Take note of the fact that, depending on the time of the year, the shape they form will not always be an upright kite.
Ensure that you are viewing the Southern Cross and not the "False Cross." In the immediate vicinity of the Southern Cross are two very bright "pointer stars," Alpha Centauri and Beta Centauri, which form a line pointing to the "top" point of the true Southern Cross. If you don't see the pointer stars, you are looking at the False Cross.