If you need to lay the corn down sideways, place the instant pot rack in the bottom of the pot.
Pour the water into the bottom of the pot. Lay the cobs down two at a time, criss-crossing each other.
If you can stand the corn on it's end, stand the corn on it's wide edge like shown in the photo.
Place the lid on the Instant Pot according to the manufacturer's instructions.
Cook on high pressure for 3 minutes, then quick release the pot according to the manufacturer's directions.
Remove the corn carefully and serve.
Notes
I have found that the corn cooks the best when placed standing up, I used my larger 8 QT instant pot for this. IF you choose smaller, shorter corn, you can stand them straight up in the smaller 6 QT.
For the best results, make sure to leave a good 1/2 inch of "handle" of cob on the end of the corn, this is the part that touches the bottom of the pot, however I have no problem with the corn ever burning.