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