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