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