Start with using a clean linen or cotton pouch to put the malted barley in it and tie it up using a string tightly. Take a bowl and pour enough warm water so that the pouch can be soaked in properly.
Just manually squeeze or press the pouch a few times in order to take out the malt powder from the barley so that it can get mixed with the warm water.
It should be done for at least 2 minutes. Now, tightly squeeze out the pouch to allow all the good liquid to come out, and then discard the left barley malt.
Allow the barley malt water to rest for about 30 minutes and this will result in making the starch sink to the bottom.
With care and no shaking of the bowl, try to pour the malt water into a different bowl, not allowing the starch to fall into the other bowl. Try to go easy here but with utmost care. Throw away the starch.
Next, add the cooked rice into the instant pot or rice cooker, whatever you are using, and break up the rice grains a little using a rice spatula or spoon.
Cover it with a lid and keep your instant pot in a warm setting. Remember that the duration of fermenting can differ from 5 - 8 hours relying on the level of heat of your equipment. But an instant pot can take up to 3 - 5 hours only whereas a rice cooker can take much longer.
Now, if you are able to see some rice grains floating above, then it means that the rice punch is fermented properly. But if that is not the case, then wait for a few hours more. But never wait for more than 8 hours as the dish will be spoiled
Add sugar & ginger slices (if preferred) and then bring it to a boil. Cook for 5 - 7 minutes. The saute setting is used here for an instant pot. (If you are using a rice cooker, then transfer the rice punch to a medium-sized pot and let it boil on the stove. Remove any foam or debris from the top if any).
Allow the sikhye to cool down totally.