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