Windscreen Misty/Marky Streaks

[Beanbag]

I was told , way back in the mists of time , to rub half a potato on the screen to improve visibility after getting a streaky screen and also when there is a frost about to protect the blades  and screen from freezing , have not tried this for any years as my car is under cover, but it used to be effective. Certainly not expensive.
It worked in the 1950's when winters were harsher and screen wash was not so effective.

[fashionphotography]

right first of all yes new wiper blades are a good idea then clean the windscreen well wash first then use a glass cleaner . then id use a brake cleaner on a cloth and wipe. . DO NOT!! use wd40.. its a lubricating oil.. also yes get the washer bottle cleaned and refill with new  washer fluid. but i wouldnt go to halfords though .