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