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