Professional house cleaners use a special tool to clean windows called a squeegee. It’s a rubber tool that’s similar to one used in your shower.

To start, you need to wet the window pane with water or cleaning solution. Then, wipe it down with a microfiber cloth. Avoid using rags, which are too dirty and often leave streaks on your windows.

Clean the Frames

Often, the frames and sills of your windows are the dirtiest part of the window. That’s because they sit in direct contact with the elements and are exposed to a lot of dust, as well as the chemicals you use to clean the glass and windowsills. A regular wiping of these surfaces can prevent major buildups.

Begin by removing any curtains or blinds that are hanging from the window frame and wiping down the wood. Be sure to use a non-ammoniated all-purpose cleaner for wood and vinyl. For more stubborn marks, you can try a paste made from baking soda and water. Or you can also use a cleaner with oxalic acid, like Zud or Bar Keepers Friend. Apply the solution and scrub, then rinse.

Once the window sills and frames are wiped down, you’re ready to start cleaning the glass itself. Use a lint-free cloth or microfiber towel to wipe away any remaining dirt and debris. Avoid paper towels or newspapers, which can leave lint behind.

Wet a clean section of the squeegee with your cleaning solution (a simple solution of washing-up liquid and warm water is fine). Once the cloth is saturated, switch to a dry towel and continue wiping. As you work, make a backward S pattern (if you’re left-handed, start at the top left corner of the window) until you’ve passed over the entire surface.

When you’re done, switch to the squeegee again and run it over the glass in an S-pattern until the window is streak free. To prevent smearing, periodically wipe the blade of the squeegee with a dry rag.

If you want to be extra sure that your windows are streak-free, you can wipe the frames with a soft cloth that’s been dipped in vinegar or distilled water. This step helps remove any residual soap and grime that may be lingering on the frames. You can then polish the frames with a dry, lint-free cloth. To help avoid streaks, you can also use a microfiber towel to buff the frame. Adding this final step to your regular cleaning routine can make your windows shine.

Wipe Down the Glass

If you’ve got a lot of buildup, spray the glass surface with a commercial cleaner or a solution of equal parts water and vinegar. Let it sit for a few minutes to soften the stuck-on gunk. Then scrub it away with a soft brush and rinse the glass surface thoroughly. You should notice the white spots disappearing in a matter of minutes.

If your windows are particularly dirty, you can use a commercial glass-cleaning product that contains oxalic acid. Apply the cleaner with a damp cloth and rub until the stains are gone. Rinse the window and wipe it dry with a lint-free cloth.

Before you spray the glass with a cleaner, cover the wood frame with newspaper or another absorbent material to protect it from drips. Many cleaners can damage the wood, so it’s best to prevent the problem.

Start at the top of the window and work your way down to avoid drips. If you have to, spray the cleaner into small sections to ensure the glass is evenly wet and to minimize the chance of over-spraying on non-glass surfaces.

Once the surface is wet, use a microfiber cloth to wipe off the cleaner, or paper towels if you prefer. Switch to a new section of the cloth as it becomes saturated with cleaner. Using microfiber cloths is the best way to avoid leaving streaks behind.

Switch to a clean section of the towel or squeegee as soon as you see any visible streaks. Wipe in an “S” pattern rather than in straight lines; this is quicker and less likely to cause water or cleaning residue to evaporate prematurely, which can lead to streaking.

If your glass is particularly streaky, you may need to repeat the process several times to get rid of the marks. When you’re finished, give the window a quick buff to shine it up and remove any remaining smudges. You can also use the same technique on mirrors and other glass surfaces in your home. And don’t forget to wipe the frame and sill of your windows, as well.

Apply the Cleaner

Whether you use a commercial window cleaner or make your own homemade vinegar solution, it’s important to apply the product generously. “It takes a lot of cleaner to dissolve and suspend the dirt, so skimping is likely to lead to streaks,” Forte says.

If you do opt to purchase a cleaning product, look for one that’s ammonia-free. Ammonia can leave behind foggy spots on some types of glass, especially car windows. Many glass cleaners also contain ingredients like alcohol, which can leave a sticky residue that attracts dust.

When applying the cleaner, it’s also helpful to have a lint-free cloth close at hand for wiping. You might also want to have a sponge on hand for stubborn stains, such as bird droppings. If you have a hard time reaching corners of the windows, you might want to invest in a squeegee. According to cleaning sensation Mrs Hinch, this device makes the job so much easier and helps guarantee a streak-free finish.

To avoid smears, start by wiping the rubber edge of your squeegee with a lint-free cloth. Next, wipe down the glass in one direction. Then, go over the same area with a second stroke, slightly overlapping the first. Once you’ve wiped down all the glass, give it a quick rinse with water.

It’s also a good idea to take this opportunity to refresh the window screens by wiping them with soapy water and a clean microfibre cloth. Finally, if you have fabric window treatments, now’s the time to shake them and run them through a short cycle in the dryer to prevent wrinkles.

Another way to keep your windows looking fresh is by adding a few drops of essential oils to your homemade window cleaning solution. Tea tree oil, for example, is not only a great cleaner but also has antibacterial and antiseptic properties. It will also leave a nice, fresh scent behind. Just remember that these solutions should never be used to clean glass surfaces with wooden frames, as they could damage them.

Use the Squeegee

Using the squeegee can be the most frustrating part of cleaning windows, but it’s also what makes them shine. The key is to use it correctly, and to understand that it won’t work if you hold it too tightly or press down on the glass. Instead, use a comfortable grip and move your hand and wrist throughout the cleaning process. If possible, get a squeegee belt or holster, to keep the handle clean, upright, and easily accessible.

Before you start cleaning the window with your squeegee, make sure it’s completely dry. Keeping it dry helps to prevent streaks and ensures the blade is able to glide across the surface without skipping or lifting. If you are not comfortable squeegeing a window, or if the frame isn’t cleaned properly, consider hiring an expert to do it for you.

Once the squeegee is dry, wet it with a sponge or lint-free cloth (to avoid drenching the window) and wipe away any excess solution from the window frame. Wetting the squeegee will help it glide smoothly over the window glass and avoid skipping. After each stroke, be sure to wipe the rubber edge of the squeegee with a dry microfiber cloth.

Wet the squeegee blade first (a dry blade will skip). Then, starting at an upper corner, begin squeezing down the window glass in a straight stroke. Overlap the previous stroke by about a inch, and continue until the entire window is cleaned.

For best results, we recommend cleaning large windows in sections rather than attempting to do them all at once. This will help you avoid drying the window cleaner before it can be removed and it will also ensure that each section is thoroughly cleaned before moving on to the next.

You’ll also need to replace the squeegee rubber regularly as it will become nicked and rounded with constant use, causing streaking. Squeegee rubbers are inexpensive and easy to find, so don’t be afraid to invest in a new one whenever you notice it’s losing its effectiveness. Ideally, it should be replaced every 2-3 months.