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