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