Have you ever spent a significant amount of time window cleaning until your glass sparkled, only to have the sunlight shine and reveal streaks and wipe marks that you left behind? One way to avoid this is to vary the direction that you wipe your windows. Just like painting a room, the best way to avoid noticeable strokes is to go over the surface several times, alternating wiping in a different direction each time.
Start by cleaning the glass using small circular motions. Don’t make the circles too big. Instead, work in a comfortable range of motion. This first pass will wipe away most of the moisture from the glass cleaner as well as eliminate many of the streaks. Follow up by going over the glass once using horizontal swipes and then once using vertical ones. Although the process takes three steps, it only takes a matter of seconds per mirror or window. It’ll be time well spent when the sunlight hits the glass and there’s not a streak in sight.