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