Click "set Birth Date" first.

Set your birth date year with the pull down arrows at the top, then click on the day on the calendar, then click OK.

Now click "set Start Date"

Now you must set the period for which you want to chart, normally that would be today, unless your desire is to see your biorythm for some time in the future.

Now just click the "Biorythm" button on the right to obtain your 30 day biorythm for the next month.