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