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