There are many flavours, I like the Couchbase install since it provides a nice Web interface for you to see what objects are in which data bucket. This post is just going to provide a simple and basic over view to get you a working memcached setup on Ubuntu 12.04
sudo dpkg -i couchbase-server-community_x86_64_1.8.1.deb
Afterwards you will see the messages
Unpacking couchbase-server (from couchbase-server-community_x86_64_1.8.1.deb) ...
Setting up couchbase-server (1.8.1) ...
* Started couchbase-server
You have successfully installed Couchbase Server.
Please browse to http://workstation-01:8091/ to configure your server.
Please refer to http://couchbase.com for additional resources.
Please note that you have to update your firewall configuration to
allow connections to the following ports: 11211, 11210, 11209, 4369,
8091 and from 21100 to 21299.
By using this software you agree to the End User License Agreement.
Processing triggers for ureadahead ...
ureadahead will be reprofiled on next reboot
Choose either Memcache or Couchbase
(on a workstation of if you aren’t logged in as root)
sudo /etc/init.d/couchbase-server start
sudo /etc/init.d/couchbase-server stop