dd if=/home/User/Downloads/ReactOS-0.4.3-live.iso of=/dev/sdb
sdb: USB stick.
And 256 MegaBytes old USB stick (perfect for 210 MB ReactOS live iso) is a way of reusing instead of
And 64 MB and older USB sticks is a way of using with FreeDOS instaled in it, with Rufustrashing it
http://rufus.akeo.ie/
According it says
(2) Non exhaustive list of ISOs Rufus is known to work with: [...] ...ReactOS,...
In the world today it is necesary to have LiveUSB, cause CDs are starting to disappear or they are not so comon as before.
Maybe in some years ReactOS LiveUSB will be full working without problems.
And in PC / Notebooks without BIOS USB support there is Plop Boot Manager
https://www.plop.at/en/bootmanager/intro.html
https://www.plop.at/en/bootmanager/full.html