Hi there. The type of foot controller you want to use is shown on the link below http://www.piedog.com/musical_instruments/pro_music_live/midi_floor_controllers/yamaha-mfc10.htm

Not sure if these works with PSR3000 but I'd imagine they do as it works great with a Tyros 2. You just go into a menu on the keyboard and it's easy to set it up for alsorts of functions including the ones you need.