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