Odoo provides official installers, for various OS types and Openerp/Odoo versions, at the Nightly repository
Download installer/package of version of your choice for your system ( Windows (.exe), Debian/Ubuntu (.deb), Redhat/CentOS(.rpm) ) from the Odoo's Nightly Repository: http://nightly.odoo.com/ and install it.
wget -O - https://nightly.odoo.com/odoo.key | apt-key add -
echo "deb http://nightly.odoo.com/8.0/nightly/deb/ ./" >> /etc/apt/sources.list
apt-get update && apt-get install odoo
yum-config-manager --add-repo=https://nightly.odoo.com/8.0/nightly/rpm/odoo.repo
yum update && yum install odoo
Examples are shown Odoo version 8.0 repository links, adapt these links to install different version by changing /8.0/
in the above repository URLs to /7.0/
for Openerp v7 or /9.0/
for Odoo v9, according your version of choice