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