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