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