I use Sprayway and a microfiber cloth.
I buy it at Home Depot. I apply the Sprayway directly onto the cloth, then wipe down the windows.
check out walmar in the automobile section, they had a big kiosk full of ice melter in a can for 50¢ on clearance. It is methanol and can be used as hand sanitizer also, don’t drink it.
Windex nasty. Alcohol’s not much better. I like real glass cleaners like that from Miller-Stephenson.
But yeah, a mild abrasive like newspaper works well. Also, dry paper-towels, not the fluffy kind, but the kind you’d find in the dispenser at work which is about the consistency of butcher-paper. Oh, that scrubs so nicely…
Also, avoid things like Armor-All on your dash if you don’t want haze that needs a razor-blade scraper to get off. That stuff outgases like crazy, hazes the inside of your windshield as it boils off.
Best thing ever for windows full stop is a well used towel roll - the sort you used to get with a rotating cotton towel. I managed to acquire one when they took our old one out about 20 years ago lol, still using it now!
Those things are stupidly well washed (maybe 100’s of times) and on windows they rule - nothing I’ve ever used comes close.
Just windex and paper towel or even better an old but clean cotton towel.
Make sure to rub it dry to prevent stains and swirls.
The best advise i can give:
DO NOT TOUCH YOUR WINDOWS!
It will always leave marks and stains, use your AC and blower as intended.
well, this didnt look at all good after some days + sunshine from the front.
I still remember it even after years and have not used this method since. 
Thanks for the tip, kennybobby.
Yeah, Armor-all looks really good, but messes the windshield up, worse than even cigarette smoke I think.
Norwex gray and purple cloth.
Wet the gray cloth, wring it out. Wipe window with the wet cloth, dry with the purple. No more streaks.
I am not affiliated with the company. I used to hate washing any windows before wifey bought these.
Invisible Glass is cleaner I use & (more importantly) these glass cleaning cloths or any other kind of lint-free polishing cloth