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