Straight from the Apple Support page:

How to create a bootable installer for macOS https://support.apple.com/en-us/HT201372

High Sierra Page https://support.apple.com/en-us/HT208969

High Sierra App Store Link (hidden from standard Search) https://itunes.apple.com/us/app/macos-high-sierra/id1246284741?ls=1&mt=12

The Manjaro Wiki suggests to make a bootable USB Stick like that:

sudo dd bs=4M if=/path/to/manjaro.iso of=/dev/sd[drive letter] status=progress oflag=sync

While this might work on Linux, it does not work with dd on OSX/Darwin. Here are the error messages:

dd: bs: illegal numeric value
bs does not understand M
multiply manually, 4M -> 4 1024 1024 -> 4194304

sudo dd bs=4194304 if=/path/to.iso of=/dev/diskNr status=progress oflag=sync

dd: unknown operand status
dd on OSX does not understand the status flag
remove status flag

sudo dd bs=4194304 if=/path/to.iso of=/dev/diskNr oflag=sync

dd: unknown operand oflag
dd on OSX does not understand the oflag oflag
remove oflag flag

sudo dd bs=4194304 if=/path/to.iso of=/dev/diskNr

dd: /dev/disk4: Resource busy
Unmount disk before use, either via umount or in Disk Utility

And here we have it:

sudo dd bs=4194304 if=/path/to.iso of=/dev/diskNr