How to transfer data from one usb to another usb without pc

You would have to have a device of some sort that would allow you to save the data from the first usb device to a neutral location and then plug the usb in and move it to the new one. Or you would have to have the ability to plug both usbs into the same device at the same time and just move it from one drive to the other.

This is assuming when you say "usb" you are talking about a jump drive. As for doing it without a computer, it would have to be done like I mentioned above.