To do that, both consoles should have B9S installed.
So the important thing here is that the target console should have CFW, if it has you can follow this steps:
Enter to GM9 on the source console.
Navigate to SYSNAND VIRTUAL, and copy the file called ctrnand_full.bin to /gm9/out.
Now insert the source's console SD Card to the target one.
Open GM9 on the target console.
Navigate to SDCARD/gm9/out and press A on the ctrnand_full.bin file.
Select CTRNAND Image Options, then transfer image to CTRNAND.
Input the combo keys and wait for it to finish.
When it finishes, reboot your console.