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