Create USB installer for Big Sur 11.6 for M1 Macs

You just need one Install macOS Big Sur.app for both Intel and M1.

Read the instructions on how to create a bootable USB.

At the bottom of the page there are instructions for booting

to the USB using M1 and Intel macs.

https://support.apple.com/en-gb/HT201372

From personal experience, make the USB Installer on the M1computer.

For some reason, preparing the USB before hand by formatting it HFS Journaled / GUID on Intel based computer and then creating the USB Installer on the M1 - the createmedia command would fail.

Had to reformat the destination drive on the M1 and presto - the media creation would work.

Do not know why, just tried several time until fell upon this oddity

So the downloaded Big Sur installer seems to be universal (i.e. it works for Intel and M1 Macs regardless on which system it was downloaded). But for some strange reason the bootable installer disk must be reformatted as Mac OS Extended (Journaled) in the same Intel or M1 Mac as where the bootable installer is then created via the same Terminal command.

I am curious whether the bootable installer then works in Intel & M1 Macs? Or must the user prepare a copy for each platform?

FWIW I have noticed that at least my Intel Mac mini 2018 must be booted twice to a freshly prepared installer and the 1st boot obviously does some extra setup to the disk.

(I do not have M1 Mac and this is just an academic question).