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