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