Hi and welcome to Just answer.
Initially, you need a voltage regulator (step down). You can order it here. CLICK THIS LINK.
First plug the goldsource into the main outlet (use an adapter that can be borrowed from the hotel or bought cheaply at any electronic store). Then plug your sewing machine into the goldsource (in front where it says output 110V). At the back of your goldsource, make sure the input voltage selector is set at 240V.
Hope this information will be helpful.
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