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