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