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