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