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