Cottage pane windows are made up many smaller glass windows, which makes them beautiful and sturdy, but far harder to clean! Like most windows, the best way to clean them is still a squeegee, but in this case, you will need a much smaller sized tool than for other window types. It will need to be at least small enough to fit into each pane, if not even smaller.
To begin cleaning, use slightly soapy water to wipe each pane down, but with cottage pane windows, there are many joins and corners, so be sure to really scrub the edges of each pane to ensure a clean finish. Then, before the glass dries off, use the squeegee to wipe all the water off the surface. If the squeegee is a tight fit for the pane, wipe in one motion from top to bottom, catching the excess water with a cloth.