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