There is also an option for converting physical 5.25 disks into 140K
image files (so they can be stored on your hardisk) using a program
called DOS 3.3 Launcher. You simply double-click on the image from
the Finder and all the same steps above are carried out and the game
or application run, only to return your Control Panel settings to normal
when you quit back to the desktop. It was somewhat limited from what
I recall though, mainly it only worked 48K RAM or less titles.
The IIGS automatically switches between native mode and emulation
mode (acting as an 8-bit Apple IIe) depending on the software run, there's
no special startup disk required or Control Panel settings required. What's
mentioned above just makes running DOS 3.3 software easier and more
automated.