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