Recording of Humidity and Temperature through Hygrometer

What is the exact procedure to record the humidity and temperature by using hygrometer?
For example, our frequency for recording of temperature and humidity is once in a shift. So, during recording of temperature and Humidity, can we record it which is shown on screen at that time or to record it by first pressing memory button and then record the max. and min. temperature and humidity?

It is better to record min, max and current all values.


record twice in a shift
in 1st half n start of 2nd half

Frequency can be proposed as:
for core area: as per 3 sifts (min, max, actual temp, actual RH)
for Non Core area: twice a day.(min, max, actual temp, actual RH)