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