For years I use Partition Magic en DriveImage, products of Powerquest, swallowed up bij Symantix nowadays. These tools offer both to make a set of bootabel floppies, to use without installing the tools. One for Caldera DOS, en the second with the program.

However most computers are now delivered without diskettedrives. The only way to boot from extern is from a CD.

Does anybody know how to make a bootable CD with Caldera DOS and the software on it ?

   If you have the bootable diskettes (and a diskette drive), you can make a bootable CD out of them.  Most CD burner software have this option.
   You might try asking the company that makes those programs or looking on their website.  Surely, they have a way to make bootable CDs.
   Other than that, there really is not an easy way to make a bootable CD for them on your own.  You could make a BartPE CD ( http://www.nu2.nu/pebuilder/ ) and then put those programs on there.  It is possible that they may not work on the CD.

I have used the Partition Magic/Caldera DOS two-floppy combination for YEARS and also use the same two-floppy combination to run DriveImage, another excellent program from Powerquest, which was really swallowed up - hook, line, and sinker - by Symantec. There seems to be no trace of Powerquest now, and Symantec wants everyone to use Ghost to copy hard drives.

Having said all that, I do two things you might want to consider:

1) I install a floppy on each new computer we buy. It costs extra, and uses up a drive bay, but it allows the continued use of Partition Magic and Drive Image.

2) I carefully guard the useability of the two floppies I've got by keeping images of both floppies on CD's. That way, when one of the floppies gets damaged or otherwise goes south, I've got a permanent backup and I create a new floppy from the CD. This approach has never left me in the lurch.

Good luck, and I'm glad there are true believers besides me out there still using Powerquest's excellent products. What a bust for them to go under. I wish they had just put all their stuff out on the web under a GNU license. The world would be a better place had that happened...