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