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