In the command line type
Press your insert key.
Insert a line, run every five minutes for example (more on syntax
http://unixhelp.ed.ac.uk/CGI/man-cgi?crontab+5)
5 * * * * /usr/bin/lynx -source <a href="http://yoursite.com/cron.php
">http://yoursite.com/cron.php
[/geshifilter-codes]
And now exit: press escape and type ":exit"
By exiting you are saving and you wont be prompted.