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