There is an Execute a Shell item on the menu. If the menu is not available when you need to use the shell, press Left Alt F2 (on a Mac keyboard, Option F2 ) to switch to the second virtual console. That's the Alt key on the left-hand side of the space bar, and the F2 function key, at the same time. This is a separate window running a Bourne shell clone called ash. At this point you are booted from the RAM disk, and there is a limited set of Unix utilities available for your use. You can see what programs are available with the command ls /bin /sbin /usr/bin /usr/sbin and by typing help. The text editor is nano. The shell has some nice features like autocompletion and history. Use the menus to perform any task that they are able to do — the shell and commands are only there in case something goes wrong. In particular, you should always use the menus, not the shell, to activate your swap partition, because the menu software can't detect that you've done this from the shell. Press Left Alt F1 to get back to menus, or type exit if you used a menu item to open the shell.