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