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