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