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