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