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)(11,14)(12,19)(13,15)(16,21)(17,23)(18,24)(20,22)(25,26)(27,33)(28,32)(29,30)(31,35)(34,40)(36,38)(37,39)(1,3,4,7)(2,5,6,8)(9,11,13,17)(10,14,15,23)(12,20,21,18)(16,24,19,22)(26,29)(28,36)(31,33)(34,37)(1,2)(3,5)(4,6)(7,8)(10,15)(11,17)(16,19)(18,20)(25,27,30,35)(26,31,29,33)(28,37,36,34)(32,40,38,39)(9,10)(11,14)(12,16)(13,15)(17,23)(18,22)(19,21)(20,24)(25,27)(26,31)(28,34)(29,33)(30,35)(32,39)(36,37)(38,40) involution — undirected(1,3)(2,5)(4,7)(6,8)(9,11)(10,14)(12,18)(13,17)(15,23)(16,22)(19,24)(20,21)(25,28)(26,32)(27,34)(29,38)(30,36)(31,39)(33,40)(35,37) involution — undirected(1,2)(3,5)(4,6)(7,8)(9,12)(10,16)(11,18)(13,21)(14,22)(15,19)(17,20)(23,24)(25,29,30,26)(27,33,35,31)(28,38,36,32)(34,40,37,39)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.