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