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