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