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