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