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