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