I would like to be able to create a disk image (that I can transfer via Disk Utility.app to a large USB storage thumb drive) which is a multiboot installer for provisioning various operating systems from a single USB drive. I need to be able to create the image in one step to include multiple bootable OS installers (various multiple versions of OS X/Windows/Linux/Linux based Recovery Platforms), all from a single OS X machine.
I found a nice tutorial for creating a multiboot usb thumbdrive via Linux that will boot OS X on a Mac, and Linux or Windows on PCs or Macs, and obviously, if I already have a Linux virtual machine, I could use YUMI as indicated in the tutorial (and I have seen other, similar tutorials that use a similar utilities to do this from Windows like SARDU and XBOOT), but I am hoping to discover a similar OS X native method or application that accomplishes the same thing.
I am aware of and own the commercial application iPartition, and obiously have access to fdisk and gpt amongst other command line utilities available for use which likely could do the job. If I knew exactly how to set up and where to place the specific individual platform partitions, then I might be able to use one of them. I'd be relatively satisfied with an answer with suggested examples of how to set up this complex partition table, with any explanation on what is particular or different about the types of partitions needed and where they go, and maybe some example syntax for the command line utilities as well.
Adding this not to answer my own question, but to help whomever answers, and I hope with even easier instructions. Maybe it can be done another way? Maybe following a guide to create a multiboot Mac would work, except instead of using the internal harddrive, install on a USB drive as though it were the internal drive, and solve the desire to be able to do this without actually having access to Linux and Windows machines. See here, here, and here. I really want instructions my mother could follow.
Best Answer
The way to do this is to create multiple partitions on the USB drive. There is a Tech Republic article that gives the full details on how to do this:
http://www.techrepublic.com/article/pro-tip-create-an-os-x-multiboot-usb-install-drive/
In summary, TechRepublic gives the steps:
Copy the relevant contents to the particular partitions. This is different for different versions of MacOS:
Apple OS X 10.7 (Lion), 10.8 (Mountain Lion):
a. Right-click the installer and select Show Package Contents from the context menu;
b. Drill-down through the Contents | Shared Support directories and drag-drop the InstallESD.dmg to the desktop;
c. Using Disk Utility's "Restore" tab, Perform a Restore into the appropriate partition, using InstallESD.dmg as the source. This takes about 30 minutes.
Apple OS X 10.4 (Tiger), 10.5 (Leopard), 10.6 (Snow Leopard):
Since these were distributed as DVDs, you restore from the DVD or ISO image. (DVD restore will be much slower than the file restore method.) Use Disk Utility's "Restore" tab with the DVD or ISO image as the source.
Apple OS X 10.9 (Mavericks) and 10.10 (Yosemite):
Ise the new "createinstallmedia" command. If your installer.app is not in /Applications, modify the "-applicationpath" argument appropriately.)
For example:
I expect that the method for 10.7 and 10.8 will work for later versions of MacOS as well.