Causing your bedroom to be darkened artificially is one way to regulate the times you sleep and wake, so that you can wake to an alarm, rather than by the sun streaming through your windows. Similarly, a catch-up snooze in the afternoon will be aided by the absence of heat and sunlight streaming into your bedroom.
Blackout curtains are a simple way to moderate the amount of light coming in through your windows. Often experienced in hotel rooms, this effect can be achieved in your own home with a single layer blockout fabric curtain, or with the use of double curtain racks – mounting a sheer curtain underneath, and second curtain layer with a blackout backing on top. The double layer insulates and allows the flexibility of privacy when the blackout is not needed.
Depending on your budget, blackout curtains are sold ready-made in big retail stores such as IKEA, Kmart or Freedom, but are usually only available in darker colours and not always tough enough to withstand the Australian sun. For best results and your choice of colour and a range of fabrics, have them custom made to fit your windows and ensure the best coverage.