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