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