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