The beginner.
Useful information: If the blood u discharged from the body of a mubtadiya (i.e. a woman whose blood has come for the first time) for more than 10 days and all the blood that has come contains signs of menses she should consider the period corresponding to the habit of her kinswomen to be menses and the remaining number of days to be istihaza. However, if she has no kinswoman or the habits of her kinswomen are different she should consider the first 6 or 7 days of the month to be the days of menses and then observe precaution till 10 days are completed. As regards the following months she should treat the first 3 days to be the days of menses and then observe precaution for 6 or 7 days.