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