Dynagen is a text-based front-end for Dynamips, which uses the “Hypervisor” mode for communication with Dynamips. This can be the way to go if you do not want to install GNS3 for whatever reason. Dynagen is no longer officially maintained (official website here); however Dynagen is still updated and developed for GNS3, this means you can download GNS3 sources, find Dynagen and start it. We are going to provide a package one this page soon.
We also intend to update the official tutorial.