Step 01
First, the amendment must be approved by an absolute majority of each house of parliament, or it must be passed twice by an absolute majority of one house, with an interval of three months in between.
Step 02
Secondly, once a constitutional amendment is put to a referendum, it has to be passed by a majority of all the electors who vote.
Step 03
Thirdly, a referendum must also be approved by a majority of voters in a majority of the states. That means that there has to be majority “yes” vote in four of the six states.