just put the floppy in the drive and type
and you should be good to go. If for any reason that doesnt work, try this
mount /dev/fd0 /mnt/floppy
to tell if it is mounted or not, simply run the
command, and look for fd0 or floppy in the list of mounted filesystems. Also, be sure to umount it when youre done, in most versions of linux, the info you put on a floppy isn't written to it until it is umounted.