How to install grub to empty disk from ubuntu liveCD

*Disclaimer: I'm a newb and I need step by step guide. Thanks!* I want to first install grub without OS, since it will boot from ISO file off the local network storage. I'm booted into a liveCD (I can't install it since I need a volatile system) I'm already stuck at first stage. I tried grub-install /dev/sda and I get error saying grub-install: error: cannot open directory '/boot/grub/i386-pc': No such file or directory. So I created and copied all files it grub-install needed and now it says grub-install: error: failed to get canonical path of 'aufs'. I searched web and figure most answers requires me to use chroot while I have a installed system (can be broken though) I don't have Ubuntu installed to any drive and my goal is to **install grub from liveCD to empty drive**. I want to start with an empty boot loader. How do I do this? Thanks again in advance.