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