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