As soon as the hair is washed, it begins to "drift snowflakes", and it can't be caught or shaken, but more and more, let's see what's wrong with your scalp
The epidermis is made up of keratinocytes, which are constantly renewed and shed, and normally few cells are shed very slowly and slowly, so we can't see visible dandruff with the naked eye, and the hair looks "flakeless".
However, when the scalp is not healthy due to certain factors, keratinocytes will shed more and more quickly, resulting in the formation of visible "snowflake" dandruff. 
The increase in oil secretion from the scalp + the excessive reproduction of Pityrosporum funrifolium promote each other, forming a vicious circle, and dandruff increases dramatically. 
About the frequency of hair washing.
Oily hair: Oily hair has strong sebum secretion, and if it is not washed in time, it may cause clogged pores, so you can increase the frequency of hair washing appropriately, once a day, or once every other day.
Dry hair: less sebum secretion, the scalp is prone to dryness and itching, and the frequency of hair washing should be reduced, 1-2 times a week.
Normal hair: 2-3 times a week, just as often as you like.
2.Don't apply shampoo directly to the scalp: take an appropriate amount of shampoo, wet it with the palm of your hand and lather it into a lather, then apply it evenly to the hair. Don't rub your scalp too hard and massage gently.
3.The water temperature should not be too high, control it at 38-40.
4.Do not apply conditioner to the scalp and leave on for up to 5 minutes, then rinse.
5.Dry your hair in time, the hair dryer should be more than 15 cm away from the scalp, and the temperature of the blow should not be too high.
Of course, there are many diseases in the family that can also cause increased dandruff, such as psoriasis, tinea capitis, lichen planus, folliculitis, asbestos pityriasis, head lice, etc., especially the increase in dandruff combined with rash, which must be timely**.