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