Launch the following command in order to identify the USB drive:
$ diskutil list
ATTENTION!! Check the correctness of the drive before launching the next command. If you specify an incorrect output you could overwrite another disk drive. Suppose the USB drive is /dev/disk2. Then proceed to copy the image on the USB device.
$ dd if=kali-linux.iso of=/dev/disk2 bs=512k
Once dd has finished imaging the drive, it will output something that looks like this:
5823+1 records in
5823+1 records out
3053371392 bytes (3.1 GB) copied, 746.211 s, 4.1 MB/s
After the installation is completed mount the USB device and replace the EFI/BOOT/ folder with the one in this repository. Reboot and Enjoy!