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