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