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