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