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