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