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