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