make a backup of your /home directory
typos when running fdisk and mkfs can delete whole filesystems. *be very careful*
turn off the computer, install the drive, turn on the computer and make sure that the new drive comes up in the bios
boot e-smith as usual and log in as root
run "fdisk /dev/hdx" and hit "p " to see any existing partitions (change x to whatever your hard disk is -- check dmesg to find out what x should be)
use "d" to delete any existing partitions, then "n" to add a linux partition (type 83) and "w" to write the partition table and exit
run "mkfs.ext2 /dev/hdx1" to make a filesystem on the the new partition (change x to...)
run "mount /dev/hdx1 /mnt/cdrom" to mount the new disk and copy over your existing home directory with "cp -ra /home/ /mnt/cdrom/" (change x to...)
run "umount /mnt/cdrom"
run "pico /etc/fstab" and add a line like this
/dev/hdx1 /home ext2 defaults 1 2
(change x to...)
run "mount -a" and then "df" to see what partitions you have and how much space is available.
the original copy of your files is still on your original disk. you should "umount /home" and then delete the original files as soon as you are happy with the new disk (ie, wait a few days to make sure that everything is working ok)