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