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