Prepare in advance for your next few car washes by making your own condensed cleaner base. Pour ¼ cup baking soda into a gallon (4 litres) bucket/jug, then add ¼ cup dishwashing liquid and enough water to fill it almost to the top. Mix well, and store the concentrate for later use. When it comes time to wash the car, mix vigorously and then pour 1 cup of the cleaner base into a water pail. Fill the pail with warm water, stir to mix, and your homemade cleaning solution is ready to use.