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