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