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