It would be reckless to consider taking a pair of scissors to cut the plastic of a regular SIM cards to make a micro-SIM. Anyone who would attempt to do so would risk damaging both their SIM and also the SIM slot of the device.
This is because regular SIM cards have not be designed and built to support such treatment which could lead to the electronic chip and tiny wires inside the card being damaged. Furthermore, if the SIM you started with is not compatible with the mobile device that uses the micro-SIM, it will be pointless. A better option would be to contact your carrier to get a micro-SIM card.
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