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