all u do is take a hammer and a small scewdriver, place it in one of the 2 holes on the back of the freewheel(the green bit) make shore your cranks are still on the bike, then undo the green bit by hitting it clockwise i think (towards the back of the bike) then once its loose take your cranks off and then take the green bit right off then with your hands take the cog thing off, now you should have the cog with all the teeth in it and sealed bearing in one hand, and all the pawls still on the crank, hopefully that made sense :">