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