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