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