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