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