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