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