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