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