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