1. Boot from your live-CD.
2. Open a terminal.
3. Launch the command
This will show you all partitions with their UUIDs and filesystems. Here for example is the output of that command on my laptop:
tobi@dragon ~ :) % blkid
/dev/sda1: UUID="1f66de30-a6a5-448f-9bad-5b7a3fe22e1c" TYPE="swap"
/dev/sda2: UUID="2bfe2395-c441-4ec5-89e9-9af815667a83" TYPE="ext4"
/dev/sda3: UUID="a1632bbd-ddf3-4337-810c-6fab59077ed1" TYPE="ext4"
/dev/sdb1: UUID="CF4A-303A" TYPE="vfat"
You can see that I have three partitions on drive sda (which is my internal disk) and one partition on an attached SD-card. The SD-card is not needed in the fstab, so we will omit that.
4. Now we will mount your Linux /-partition, in my case it is sda2:
sudo mount /dev/sda2 /mnt
You now can access all files on that partition under /mnt.
5. Create a new fstab in the mounted partition:
sudo vim /mnt/etc/fstab
Substitute vim in this command with your favorite text-editor.
6. At first we add some mounts that are necessary for a system to run properly, I just copied the entries from my fstab, you may want to have a look at your live CD's fstab to compare:
devpts /dev/pts devpts gid=5,mode=620 0 0
proc /proc proc defaults 0 0
tmpfs /dev/shm tmpfs defaults 0 0
7. Now we add the partitions:
UUID="1f66de30-a6a5-448f-9bad-5b7a3fe22e1c" swap swap defaults 0 0
UUID="2bfe2395-c441-4ec5-89e9-9af815667a83" / ext4 defaults 0 1
UUID="a1632bbd-ddf3-4337-810c-6fab59077ed1" /home ext4 defaults 0 1
Of course you have to adapt that to your needs. Substitude my UUIDs with the ones shown to you from the blkid-command. Also, if you don't have a separate /home-partition just omit that line.
8. Save that file and close the editor.
9. Unmount the partition:
10 Reboot and look if it works.