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