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