Infrastructure Software

I am going to install the vmtool on guest os linux but i am not able to do it.
i am follow these instructions

step1 : go to vm setting of maching and click on install vmtool ..
after that i display a message in the bottom of machine which is mount the cd rom ,launched the terminal and uncompress the installer.
i also saw that a cdrom icon is display on my desktop which is i think iso image.i click on it but it is empty.

step2: i create a dir in /mnt like
mkdir /mnt/cdrom

Step3 : mount /dev/cdrom /mnt/cdrom

at this step this return no meduim found..
what is this....
i can't able to go to further step untill my cdrom is not mounted.
how i can do this.....
please help from expert...................