If this is a first-time installation, point your browser to 
http://${VHOST_HOSTNAME}${VHOST_APPDIR}/zc_install/ 
to finish your installation.

If this is an update, please read below.
To update your database, go to ${MY_HTDOCSDIR}/zc_install and execute
'mysql -u root -p -D zencart < mysql_upgrade_zencart_124_to_125.sql'
with the appropriate .sql file