Make sure you have downloaded the full iSE Distribution Archive at
http://www.leveltendesign.com/l10apps/cms/download.
To install follow the installation steps
1) Verify system requirements (see
http://drupal.org/requirements)
2) Upload and unpack the Distribution Archive to your web server. You can do this by uploading the compressed file (.zip/.tar) to your server and uncompressing it with a server utility or uncompressing on your desktop and unloading all the uncompressed files.
Note: upload the Distribution Archive into whatever directory on your web server will be the root of your CMS. This typically is the www root, however might be a subdirectory of www root for testing or a site in a subdirectory.
3) Grant write permissions on: (see
http://drupal.org/getting-started/6/install/set-permissions)
a) Configuration file (sites/default/settings.php)
b) Files directory (sites/default/files)
4) Create a database for your site. (see
http://drupal.org/getting-started/6/install/create-database)
5) Run the install script. Open a web browser and navigate to your installation of the Distribution. You will be redirected to the install.php file to begin installation. (see
http://drupal.org/getting-started/6/install/run-script). On the first screen of the installation you may be asked to select which profile you want to install; Drupal or Essentials. Select the Essentials radio button.
6) To complete the installation, follow the instructions provided by the install script.