High Sierra - Bootable USB - Can't make I have a problem with making bootable USB.

I'm getting this error: 

Macintosh:~ **$ sudo /Applications/Install\ macOS\ High\ Sierra.app/Contents/Resources/createinstallmedia --volume /Volumes/Untitled --applicationpath /Applications/Install\ macOS\ High\ Sierra.app
Ready to start.
To continue we need to erase the volume at /Volumes/Untitled.
If you wish to continue type (Y) then press return: y
APFS disks may not be used as bootable install media.


On the same usb drive I had Yosemite, but for some reason I can't make it work with High Sierra. Also tried to erase it in Disk Utility(no errors).

Can somebody help?
I think the message is quite straightforward: It seems like your USB stick is formatted as APFS and the error message says that you can't.

Reformat the USB Stick using Mac OS Extended instead.