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