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