Bucket: Using a large, clean bucket is best to avoid dirtying your clean water too quickly.
Squeegee: A good squeegee will make window washing much easier. Look for one with a comfortable grip and a good rubber blade.
Sponge: A soft sponge will help you avoid scratching your windows.
Window Solution: Experts use a commercial window cleaner or make your own with vinegar and water.
Ladder: If you have high windows, experts will need a ladder to reach them. Be sure to use a stable ladder and follow all safety precautions.