Heat the iOpener for thirty seconds.

Depending on the wattage of your microwave, more or less time may be required. The iOpener is sufficiently heated when it's barely too hot to touch.

Throughout the repair procedure, as the iOpener cools, reheat it in the microwave for an additional thirty seconds at a time.

Be careful not to overheat the iOpener during the repair. Overheating may cause the iOpener to burst. Do not attempt to heat over 100˚C (212˚F).

Never touch the iOpener if it appears swollen.

If the iOpener is still too hot in the middle to touch, continue using it while waiting for it to cool down some more before reheating. A properly heated iOpener should stay warm for up to 10 minutes.