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