Technique and towels.
In direct sunlight when the windows have had a chance to heat up, cleaning glass is just a bad idea - using any product. If I simply MUST clean my windows while the glass is hot, here is what I do:
1) Move to a shaded area
2) Using a taller nap 12x12 microfiber, folded half, then half again, spray glass cleaner directly onto the glass until it is mostly covered. The additional fluid helps cool the glass surface.
3) Wipe horizontally, covering the entire surface.
4) Flip to a dry side and wipe dry.
5) Mist the glass lightly with cleaner 6) Using a glass microfiber folded half then half again, wipe horizontally until the mist has been spread over the surface
7) Flip the microfiber to the dry side and buff horizontally until streaks are gone
Keep practicing!