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