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