Actually CodeIgniter framework (CI) is nearly zero configuration. First is to put your CI files to your webserver, in this example will be using the web root directory of my webserver.

Host : www.johnbernardabella.com
Database : localhost
Username : test
Password : test

After we need to modify system\application\config\config.php

Look for :

$config['base_url'] = ''

change to :

$config['base_url'] = "http://www.johnbernardabella.com/" //for we are using the web root of the server

Then Save.

Second is to open system\application\config\database.php

$db['default']['hostname'] = "localhost"; //Host of the database
$db['default']['username'] = "test"; //Username of the database
$db['default']['password'] = "test"; //Password of the database
$db['default']['database'] = "test"; // Database Name
$db['default']['dbdriver'] = "mysql"; // Database driver for this example I use mysql
$db['default']['dbprefix'] = ""; // Database prefix
$db['default']['pconnect'] = FALSE; // Connection type (pconnect of connect)

and you CI is now configured, it now able to connect the database.

Next topic would be tweaking defualt CI configuration.