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