How to unlock a CDMA IPhone 4 to make it work on a SIM card?

I'm gonna buy a used IPhone 4 CDMA. But I wanna make it work on mobile service provider. How can I do that?

Not happening.

You can't. The CDMA iPhone 4 doesn't have a SIM card slot.

For the record CDMA carriers are also mobile service providers. As far as doing what you want, not possible. The iPhone 4 was sold in GSM & CDMA variants but only can work on one or the other. Not both nor can it be converted between them.

CDMA and GSM are two different things. There's a way you switch if you can flash the iphone.look for flashing stores usually in flea markets.

It is not possible sorry.