Find Echelon's selfboot Kit/FAQ and go on it.
The only thing: you need some prog to extract files from the image (.iso, .cdi, .nrg or so) to the hard drive: try ISOBuster. The only thing you need then - is the brain and stright hands
In most cases .cdi is already selfbootable - so, make sure it's not self-bootable first. If so then go on and make yourself a favor on making this game self-bootable.
Any questions - post here as detailed as you can....