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