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