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