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)(11,12)(13,16)(14,15)(25,26,29,32)(27,30,35,33)(28,36,37,31)(34,39,40,38)(2,5)(6,7)(9,11,13,15)(10,14,16,12)(18,22)(23,24)(28,37)(31,36)(34,40)(38,39)(1,3,4,8)(2,6,5,7)(9,12,13,14)(10,15,16,11)(17,18)(19,23)(20,24)(21,22)(25,26)(27,33)(28,31)(29,32)(30,35)(34,39)(36,37)(38,40)(1,3)(2,6)(4,8)(5,7)(9,12)(10,11)(13,14)(15,16)(17,19,21,20)(18,23,22,24)(25,27)(26,30)(28,34)(29,35)(31,38)(32,33)(36,39)(37,40)(1,2)(3,7)(4,5)(6,8)(9,11)(10,14)(12,16)(13,15)(17,20,21,19)(18,24,22,23)(25,28,29,37)(26,31,32,36)(27,34,35,40)(30,38,33,39)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.