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