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