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