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