Before I begin, I remove the storm windows.
Next, I scrape any loose or cracked paint, stain, caulk, window glazing, and other materials. I identify areas in need of repair and likely causes of the various paint failures. For instance, if paint is peeling in large sheets on the outside of a bathroom wall, I would think that moisture from the bathroom may have caused the failure. A vent fan may be in order. Or, if paint is peeling in large strips uniformly and the lap boards in wood siding have been caulked where they overlap (a common mistake in house painting) the caulk must be removed. The siding must be able to "breath" out water vapor trapped in the house. If the paint has peeled immaturely, as in the case of isolated or systemic moisture related peeling, I feather the edges between the bare wood and the paint with a sander to reduce the visual impact of the transition and ensure optimal adhesion.
Second, I replace or repair siding or trim as necessary and recommend modifications, where applicable, to better protect the deteriorated areas in the future.
Third, I wash every surface of the house. For this step, I use detergent, bleach, and a scrub brush. I do not use a power washer. I strongly prefer the control, thoroughness, and limited saturation offered by washing a house by hand. Water and dirt are not forced into the wood, allowing faster drying, less damage to wood fibers, a closer inspection process, and a cleaner house.
Once the moisture meter indicates that the house is dry enough to appropriately accept paint, I begin priming. I prime all areas or parts depending on the condition of the house.
After priming, I apply glazing compound if restoring original windows.
Next, I brush two coats on the trim and windows. Finally, I roll on and brush out two coats on the siding. I brush out paint because, in my experience, it seems to provide the best coverage with the least unnecessary paint build up, the best adhesion and, in my opinion, the best appearance possible.
Last, I wash the window sashes, storm panes and screens, make any necessary repairs or replacements, and put the storm windows back in.