Change the power steering fluid. Use a hand pump, or turkey baster (really!) to draw the p/s fluid from the p/s reservoir. Refill the p/s reservoir. Run the engine a few seconds, while turning the wheels full left and full right. Draw the p/s fluid out (again) and refill with fresh p/s fluid. You could do this once, or twice, more, if you wished to ensure the greatest amount of fresh p/s fluid in the system.