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