What good Linux utilities can i use for making images

Hello members

I would like to the know the various utilities that i can use for making .iso, .img files and also a bootable USB. I have tried to use the dd command but the USB drive does not seem to boot as needed.
I need both command line and GUI utilities. I am currently using Fedora and Linux mint on my machine. Any links to some utilities plus guidelines will be appreciated.

Thanks