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