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