Recent versions of Windows have included a program called Remote Desktop Connection. It is also available for Mac users in the App Store. This is a good way to connect to remus or romulus. Begin by searching for the program on your machine, and then run it.
In the first dialog box, give "remus.amherst.edu" or "romulus.amherst.edu" as the name of the machine that you're trying to access. You'll probably then be told that the identity of the remote computer cannot be verified. It's OK to click "yes" to continue. (We'll get this fixed.) Then give your username and password.
This gives you a Unix desktop, which you can use in many ways. A good way to get started is to run Applications>System Tools>Terminal. This gives you an initial terminal window.
There are two ways to exit Remote Desktop Connection. Best is to choose System>Logout. This terminates your programs on the remote machine and logs you out. The other way is to pick the X in the blue bar at the top of the screen. This closes the RDC program but preserves your session. You can later return to the very same session. This ability to return to an active session can be useful, but please note that the active session will continue to use system resources.