Initially it seemed cumbersome
Had to first figure out what version of Clonzilla to download and ultimately for my older computer I chose the 486 version and chose to make a iso copy of download onto a cd as opposed to usb drive.

There are several web sites that give you "step by step"

The partition issue ie what to do with the extra space is not explained well in any of the web sites so thank you. I would rate the difficulty as 3-4/10.
The only part that made me nervous was properly identifying the source and target but it is easy. However I am sure some people wipe out the source disk if they do not pay attention.