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