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