Assemble the cleaner as shown in the instructions.  The buffing pads are 1" diameter wool felt and I used two each per side.  The ones I use are for a Dremel tool and can be found at most hardware/tool stores.  Use a hobby or other sharp knife to cut a small "X" pattern at the center hole of the pad to ease installation.  Press the wedge belt pulleys tight on either side of the pads to secure them and then position them so that they are over the track.  Be sure to leave extra pad to both the inside and outside to maintain contact while going through corners.  I used Goo Gone on the pads to clean the track.

I ran this around a small oval (2 straight track between the main curves) and it cleaned the track very well.  I also tested this over switches and it negotiated them with no problem.