This portable app Macrorit Partition Expert is able to create bootable USB/CD now with the 4.0.0 Version release, it makes managing disk easier and faster in WinPE system on bootable media. Portable package of this partition software is small in size and truly portable files for Windows to resize move and to do many other operations on the disk.
A USB drive can carry portable applications. A portable application (portable app), sometimes also called standalone, is a program designed to run on a compatible computer without being installed leaving the computer's configuration information intact.
Or you can find another definition of this portable app:
A portable application is software that can be used from portable storage devices such as USB flash drives, digital audio players, PDAs or external hard drives. To be considered for inclusion, an application must be executable on multiple computers from removable storage without installation, and without writing settings or data onto a computer's non-removable storage.
In the compressed package, we can directly run the program by double-click
dm.exe. Normally when we run exe file, it opens the installation window first, you have to choose a path to install and click many NEXTs to open the software, but this exe file in the portable zip can directly open Partition Expert. So just put it in USB flash drives and it works the same like the installed edition.
Check the main window of Partition Expert, on the left top, under "Tools" tab, there is an option of "Build Bootable CD", click on it, and follow the guide, and you'll get the ISO file in about one minute
To make it's easier to find, we set the default path of ISO file on the desktop, you can change it to other path, of course. The final step is to burn ISO file to CD or other recordable device, USB, ie. Insert it and double-click the file to burn, if you're using Windows 7 and above system, there's no need to download third-party burning tool, Windows itself has powerful utility to accomplish this. Here's the complete guide on how to build bootable CD in Partition Expert
Also check Free download partition magic portable guide