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