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