The short ad easy method is :
Open x-termianl and type:
root
apt-get install root
apt-get install nitdroid-installer
then, open new x-terminal type:
root
cd /home/user/MyDocs/
then,
bzip2 -d NITDroid-0.0.9.tar.bz2

THEN WAIT FOR SOMETIME
cd /home
mkdir /and
cd /
mount /home /and
cd /and
tar xvf /home/user/MyDocs/NITDroid-0.0.9.tar
dpkg -i /home/user/MyDocs/nitdroidkernel-2.6.28-06_final1_armel.deb
Then it will send the files to correct place
the last is
leafpad /etc/multiboot.d/1 (then press tab on the screen)

NOTE
You should have install multiboot and leafpad software installed

Now enjoy!!!