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