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