Contrary to popular belief, paper towels and newspapers do not make effective glass cleaners. In fact, they could complicate your cleaning quandary by leaving behind lint, dust, or even newsprint residue (as many papers today have switched from petroleum-based ink to one starring soy). So save the paper products for spills, and stock your cleaning closet with a few high-quality microfiber cloths—perhaps the best weapons for eliminating stubborn streaks. But stick to the thin ones: A flat-weave microfiber cloth works more efficiently than its thicker terrycloth cousin because it won’t hold any lint or other particles that could transfer to the mirror and contribute to streaks.