Glad I could help :)
If you just want it to back up the home directory of the user launching the script, all you reall have to do is declare the directory you want to back up and take out the 'for' loop. I'd probably do something like this:
#!/bin/bash
FTPUSER=sanders
FTPPASS=law123
SERVERIP="192.168.1.37"
DATE=`date +%D`
echo "mirror -R $HOME $USER" | lftp -u $FTPUSER,$FTPPASS $SERVERIP
echo "Backup of $HOME complete for $USER"
$USER and $HOME are environment variables that *should* be available to the script, otherwise you can set it with something like 'whoami', or just by setting it manually.