It is very simple but till you describe which switch and which problem
then we can't help you.
But since you do not know then you are not qualified to do it.
Electrical work in Australia MUST be done by a licensed electrician.
Do the right thing - ring an electrician.
In Australia it's an obligation - not a choice. Sorry.
To give advice would be potentially negligent, no matter how simple the
problem may be.
Wiring systems vary, and with increased complexity, advanced skills and
knowledge are required. The wiring may require replacing at the same time if
it is as old as your round switch. Older 'rubber' insulated cables can
become very brittle and expose bare conductors.
I didn't help you with replacing the switch yourself, but I hope I have
encourage you to engage an electrician for the job. Spend the dollars - stay
Registered Electrical Contractor
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