RedHat 4.0 to RedHat 8.0
 

What are some general steps I hould follow when upgrading from RedHat Linux 4.0 to RedHat Linux 8.0 ?

Thanks in advance.

It's just like a fresh install, the difference is too big. If you have a separate partition for /home, don't format it when installing 9.0. If you don't have it, copy all important data from /home and other places (maybe valuable configuration files) to another machine (or, if you've got another system on the same machine, to that system's partitions).