osCommerce, probably the most widely used freeware shopping cart solutions, is really easy to install.
Simply download necessary files from http://www.oscommerce.com/solutions/downloads
Unzip the archive and upload the catalog directory to the root of your webserver.
Once uploading is done, point your browser to http://www.yourdomain.com/catalog/
You will be entering into step-by-step installation process.
Before Installation:
Do not forget to create a mySQL database, with UserID and Password to access it. You need to supply them while installing the osCommerce.
Configurations.
osCommerce configuration settings are saved in two files:
1. for administrative access
/admin/includes/configure.php
2. for user-level access
/catalog/includes/configure.php
Once installation is finished, you can straightaway jump to your admin control panel for necessary configuration.
However, if you get database connection error: check your database settings in the above two files. This is a mere hint but it is likely to be very helpful for the beginners as well.
Feel free to contact me for further assistance.
Thanks.