Here are the steps I use
1) stoners invisible glass. Get the glass wet
2) use a razor blade to get most of the gunk off. The stoners acts as a lubricant. This will remove any bug guts etc
3) dry window with a glass cleaning micro fiber towel
4) using a micro fiber polishing pad polish the glass with Gel-Gloss kitchen and bath cleaner and polish (ACE hardware), or you can use Bonami (make a paste). The key is to polish still the surface is smooth. You will feel any etching as you polish, keep going still it no longer grabs or squeaks.
5) wipe off polish residue with a microfiber (medium nap)
6) clean the glass with stoners. Use 2 glass micro fiber towels (the shorter the nap the better). Saturate one towel, wipe down the glass, immediately use the other towel to wipe and polish off the stoners (if the dry towel sticks, just go slower - let the microfiber do the work). It is easiest to do the edges first and move to the center.
If you are going to do a glass coating...
7) take your dry towel and saturate it with IPA (15%). Wipe down the glass and dry / polish with another glass microfiber towel. This will remove any wax and decontaminate the glass in preparation for a coating. I do the when ever I wax the car to make sure the glass stays clear. Be careful doing this as the IPA will remove your wax - stay on the glass.
8) Apply your coating
9) clean the inside of the class using step 6
Hope this helps. I hate dirty glass. If anyone has suggestions on improving my technique, please let me know.. Feed back please
Just did this today (sorry picture is upside down)