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