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