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