pathfinder 1e – What action do I need to fall prone

I am looking for information what action I have to use when I want to go prone like lay flat on the floor. I can as a swift action stand up from prone and want to duck behind a table stand up shoot fall prone again. Just in case it is a swift action, can I interchange a swift with a move action? So I can usw my swift to stand up, a standard to shoot and a move to fall prone?