How to use DSK and CAS files with ESP-32 CoCo?

I've been having loads of fun remembering BASIC and working through
some stuff in the Extended Color BASIC manual! But now I want to
actually save off some stuff. Keep in mind I've been out of the
emulation world for well over 10 years so I'm sorry if these are old
hat questions.

How do I use the virtual cassette feature of the ESP-32 CoCo? I
realize I have to use the F12 menu to "mount" a cassette file. But do
I have to make a .CAS file on the SD card for everything I want to
save? Or is a .CAS file like an actual cassette in that I can save
multiple things to it? And if I can save multiple things to it how do
I skip over what's already on it when I save something new rather than
overwriting? And how do I make a .CAS file in the first place?

I have similar questions for disk files. I know that for *existing*
.DSK files I can put them on the SD card and then "mount" them from
the F12 menu. But how do I make new ones? Googling seems to indicate
using MAME's imgtool. But will that make a formatted "disk" that the
ESP-32 CoCo can start using? Or do I have to DSKINI it once I "mount"
the image on a drive?

Thank you!

-- 
Rich Carreiro             [email protected]
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