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