One vertex per element, one color per generator, with an edge from x to x·s.
(1,2)(3,6)(4,7)(5,8)(9,10,14,20,15,18,13,19)(11,21,24,31,25,16,23,32)(12,26,27,34,28,35,29,17)(22,36,37,30,38,40,39,33)(1,2)(3,7)(4,6)(5,8)(9,11,15,25)(10,16,18,21)(12,22,28,38)(13,24,14,23)(17,33,34,30)(19,32,20,31)(26,40,35,36)(27,39,29,37)(2,6)(3,4)(7,8)(9,12)(10,17,18,34)(11,22)(13,27)(14,29)(15,28)(16,30,21,33)(19,26,20,35)(23,37)(24,39)(25,38)(31,40,32,36)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.