how do i change power steering fluid

Most of the time when a P/S flush is done, a chemical is added to help remove varnish and deposits(that is why you fluid looks bad). If you have not had a component failure(pump, rack and pinion, hoses, or sensor) I would suggest that you suck out the fluid in your reservoir, and add new. Repeat process until the fluid is a clean, new fluid color. Not a perfect process, but will work. Be shure to start vehicle between fills and turn the wheel back and forth to get the fluid down into the rest of the system. But to avoid getting air into it, shut off vehicle before draining the fluid again.