So, here is a few things I do, and for what its worth, I spend a lot of time detailing my cars when possible.
After a full car wash...
Starting with exterior of the glass, I clay bar it, just like how I would clay bar any paint. A lot of people feel that this step is redundant, I disagree. You can remove hard water stain like marks through claybaring.
Then I do invisible glass and any soft microfiber towel to buff it out. (inside and out)
I then follow up with a glass microfiber towel to buff out any "streaks" from the glass, just dry rub it, or a light mist of invisible glass on the towel for stubborn streaks. Glass microfiber cloth looks like your eyeglasses cloth, its flat smooth and.. not puffy at all.
Then I end with something like an application of rain-x or similar products to "seal" the glass.
If its the first time doing your windows I feel its also worth it to clay the inside of the glass too (but this might just be overkill and messy if not careful).