Mounting a directory in DosBox can bee accomplished fairly easily, you simply need to type in the MOUNT command, followed by the drive letter that you want, and the path to the directory that you would like to mount as your DosBox c:\.
The following command will mount the DOSC directory, located in your real c:\ on your hard drive:
MOUNT C C:\DOSC
The DosBox Options
The process can be simplified by entering the command in the DosBox Options file, somewhere at the bottom of the file, in the autoexec section. It should end up looking somewhat like the below example:
[autoexec] # Lines in this section will be run at startup. # You can put your MOUNT lines here. MOUNT C C:\DOSC
Basic commands for navigation
When you start DosBox, you will see "Z:\>" prompt, this simply shows your current location. To change to the newly mounted C drive, simply type the drive letter followed by colon.
To list the directories, type "dir" and hit enter. To change to another directory, type "cd DirctoryName" and hit enter, to go up in the directory tree, type "cd.." and hit enter. This is basically the standard DOS commands.