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