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