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