One vertex per element, one color per generator, with an edge from x to x·s.
(9,10)(11,17)(12,15)(13,16)(14,19)(18,23)(20,22)(21,24)(25,26,30,35,31,34,37,36)(27,32,29,28,38,39,40,33)(2,6)(3,4)(9,11,13,19)(10,14,16,17)(12,20,21,18)(15,23,24,22)(25,27,31,38)(26,32,34,39)(28,36,33,35)(29,37,40,30)(1,2)(3,8)(4,7)(5,6)(25,28,31,33)(26,29,34,40)(27,36,38,35)(30,32,37,39)(1,3,5,4)(2,7,6,8)(9,12,13,21)(10,15,16,24)(11,18,19,20)(14,22,17,23)(25,29)(26,33)(27,37)(28,34)(30,38)(31,40)(32,35)(36,39)(1,4,5,3)(2,7,6,8)(10,16)(14,17)(15,24)(22,23)(26,34)(27,38)(29,40)(35,36)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.