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