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