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