First format your usb / flash drive with FAT. Then copy all the contents of the installer .iso onto the drive.
Next delete isolinux.bin and rename isolinux.cfg to syslinux.cfg
Edit syslinux.cfg and append “usb” to the line starting with “append” … i.e. similar to this
append vmkboot.gz — vmkernel.gz — sys.vgz — cim.vgz — ienviron.tgz — image.tgz — install.tgz usb
Next grab the latest syslinux.exe (zip for windows) from here and run syslinux -s –ma <driveletter>:
Done.