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