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