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