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