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