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