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