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