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