Multisite installation help

I use Yahoo as my web host. I have installed Gallery 2.3 successfully but now would like to install it for multisite. I do not understand what to enter in the filesystem path for the multisite g2 installation. I tried about everything but could not get it to work. Error said directory did not exist. The examples are:

/var/www/example/galler2

I tried using my directory that worked with standard installation and different variations of it and the example.

I could use some assistance please.