Modern phones have a slot for Sim card is not standard, and reduced size.
the chip itself is a standard, different only plastic base on which the chip is bonded.
There are some forms of Sim factors, micro sim, nano sim they all have the same chip card differs only in the size of the plastic on which the chip.
The photo shows which slot is the size of the induced under the above sim card.
Now let's see what kind of shape is the chip on the SIM card
As can be seen chips sim cards are a little different in form, but the chips have to meet the following conditions, one of the sectors of the SIM card should end up on contacts sim slot. The first map of the largest chip but as you can see some of the contact pads are not used. A third example has a shorter length, the fourth longer.
So our task when cutting to do so that would be after you install the card into the phone pad penetrated the necessary contacts slot.
Now overlay on top of existing micro SIM card matrix.
Small little bit clipped but try anyway.
Pruning is completed, the recommendation is still not advisable to cut on the pads, as is theoretically possible shorting contacts tiny sawdust foil layer.
Since nano is sim has a size just on the chip is old SIM card should be cut on the foil, the size of nano sim imposed below, but the new sim card with a reduced chip type cut just on the size of the chip.