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