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