I like a simple vinegar water mixture to clean my windows, but regardless of what you use, if you want crystal clear, streak free panes, there are two keys factors to remember.
Dry the windows as quickly as possible. Don’t let them air dry.
Do NOT use absorbent or extra thick paper towel. The oils and chemicals that are added to the paper to make it soft and absorbent are the very elements that will leave streaks on your windows. Newspaper or brown paper works the best.