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