You can find archived versions of Kali, including the 2018.4 release, on the Old Kali Images repository. kali-linux-2018.4-amd64.iso Size: Approximately 2.9 GiB .
Use a tool like Rufus to write the ISO to a USB drive (at least 8 GB). Configure BIOS/UEFI: kali linux 64 bits 20184 iso 3 go install