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