"Installing" is a bit of a misnomer. One does not install E3SM like system software: in a location such as /usr/local/bin for everyone to use. Instead, a user creates executables for their cases and keeps them in their own directories.
The steps for supported and unsupported machines are in Installing E3SM on a cluster or HPC platform. If your machine doesn't have the necessary system software, some help is in the pages below.
NOTE: The Infrastructure Group can provide no support for porting the model to a machine that isn't designated for support under the E3SM Project.