...You can use any iso writer to create a USB stick with Jamulus 0S. If you planned to make change to the OS (settings, adding software ...), you can create a persistent live usb stick using Rufus (Windows) or mkusb (Linux).
If your hardware is old but you have a sound card with lowlatency capability or experienced problem with your actual OS and don't want to modify your hard drive then you should give it a try.
For example, I setup a 2009 PC with Jamulus OS and used a recent sound card like Zoom U22 and an old one UCA202 Berhinger ... ...