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