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