Windows should be cleaned last, as they will pick up splatter, overspray and even drag marks from toweling as you wipe the dash or window wells. Cleaning the door panels and headliners can also leave residue on the windows, so it is always best to leave them until next-to last. Most glass cleaners are used as purchased, but some professional cleaners, such as Diamond Professional Glass Cleaner need to be diluted. Be sure to read the directions on the bottle to see if dilution is necessary. When applying glass cleaner, use an absorbent, lint-free cloth, such as a microfiber towel a clean paper towel or a high-quality cotton towel. If possible use one towel to apply window cleaner and a different one to wipe the windows clean.
To begin cleaning, lower the windows slightly so you can get the top of the window pane. Then close the window and clean the bottom. Spray the cleaner liberally on the window, avoiding runs. Wipe in one direction during the first wiping application. Use the towel to wipe the cleaner off and let the window dry a minute. Once the window is wiped clean, flip your towel to the other side and wipe in the opposite direction to remove any remaining streaks.