When it comes to cleaning outside windows, things depend on the type of window you have in your home. New homes, or homes with newly replaced windows, are likely to have tilt-in or easy-to-remove panes designed with simplified cleaning in mind. The rest of us are going to need a few things for the job: a garden hose, a ladder, a bucket of clean water, a bucket of cleaning solution (this could be a bucket of soapy water made with a few drops of dishwashing soap), a cloth-headed brush or natural sponge, a squeegee and dry, lint-free cloths (microfiber works well). Be careful when choosing the right tool for your outside window cleaning job: While a power washer may make quick work of window cleaning, rent or purchase a light-duty washer and always start on the lowest setting -- spraying windows with high-pressure water streams may cause the glass to break.
Begin by wetting the windows -- give each outdoor window a good spray with your garden hose before applying a soapy glass cleaning solution. If you have more than one story, begin with the highest window and work your way to ground level; and if you're working on a ladder, make sure you take safety precautions and have a spotter close-by if at all possible.
Working one window at a time, use the cloth-headed brush or large sponge to soap up each wet window; this is going to loosen up the debris stuck to the glass, including anything stuck in the corners. The next tool from your bag of cleaning tricks will be the squeegee. Remove the soapy water (or whatever your preferred cleaning solution) with your squeegee (a long-handled or telescopic type may be easier to work with, but it will depend on your windows and your personal window-cleaning style), and wipe the blade with a lint-free cloth after each pull. Dry each window with a clean, lint-free cloth, and don't forget to wipe windowsills with a dry rag.
For a crystal-clear view, use a straight-edge razor blade to remove any paint drips on window glass from the last time the HOA painted.