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