If you want a script to run every 5 minutes, it will be for every hour, of every day, of every month, so, all values will be * execept the minute. If you want every 5 of something, it would be all minutes, every 5, or */5
day of month: *
day of week: *
command: your script
Cron just matches all time values with the current time. If they all match, it will run it.