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