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