Set up a ladder with both of the feet planted firmly on a flat surface on the ground. Place the ladder under the opposite end from the downspout. Raise the extension and rest it firmly against the roof edge or gutter.
Toss a rope onto the roof near the ladder. Have the rope nearby so that you can haul up a bucket, tools and the spout end of a hose.
Climb the ladder carefully. Have someone hold the bottom of the ladder if you need to climb from the ladder onto the roof.
Use the rope to pull up the tools you will need. Pull carefully so the bucket doesn't tip over and cause falling items to strike someone on the ground.
Begin pulling leaves and debris from the gutter, working from the end furthest away from the downspout. Use your hands or a small garden trowel to loosen and remove any thick layers of debris.
Climb down the ladder and move it toward the spout end of the gutter as you work. Take care not to reach too far while standing on a ladder to avoid falling. Continue to work until you have reached the spout end of the gutter.
Use the hose to spray a heavy stream of water through the downspout to make sure it is not clogged. Spray until water flows freely through the spout.
Move the ladder back to the opposite end of gutter. Spray water into the gutter, toward the downspout. Continue to spray water until the gutter is clean and no blockages are keeping water from running through the spout.