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