Streak free windows?

Windows are a pain to get right.

I start off by spraying liberal amounts of glass cleaner on the windshield (or whatever piece of glass I'm working on) and scrape off all the bug guts with a razor blade. Get the angle right so you don't damage the glass, or use a plastic razor blade. I then go over everything with a clay bar to pick up any small pieces of dirt or debris.

Once all the junk is off the glass I'll mist the surface with glass cleaner (I opt for Stoners Invisible Glass) and wipe it down with a low pile microfiber glass towel. I wipe up and down and then I will do another pass that's side to side. I'll then buff off any streaks with a low pile waffle weave microfiber towel. Speed is your friend. Clean your wipers too before laying them back on the glass. On the inside, sit in the passenger seat and spray some glass cleaner on a microfiber glass towel, wipe the window down, switch to a low pile waffle weave, buff off any remaining streaks. Repeat if necessary.

The key is doing all of this on a cool window. Never do it out in the sunlight and make sure there's no grease on the glass or else you'll just smear it around. When I'm faced with greasy glass I'll spray it down with degreaser and wipe with a microfiber until it's clean then i'll start the glass cleaning process as outlined above.

You can also buy anti fog stuff for your glass. I've got some at the house but I forget what it's called. Cleaning glass correctly is a huge pain but if you do it right you'll be pleased with the results.