Setting up lvm2 before installing Ubuntu

Get a terminal, root and install lvm2:

ctrl-alt-f2
sudo -s
apt-get install lvm2 -y

If you have undetected volumes:
 vgchange -ay

To setup partitions for physical volumes:

fdisk /dev/sda
p
t
1
8e
w 

To setup volumes:

pvcreate /dev/sda1

vgcreate vgLabel /dev/sda1
lvcreate -n lvLabel -L SizeG vgLabel