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