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