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