You need two config files for lighttpd, which are usually in the following two locations:
/etc/lighttpd2/lighttpd.conf: the main config, see Main Configuration. It can be split into multiple files, see Includes.
/etc/lighttpd2/angel.conf: the angel config, see Angel Configuration.
contrib/ directory in the sources includes example config files.
Then start lighttpd2 with:
/usr/sbin/lighttpd2 -c /etc/lighttpd2/angel.conf