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