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)(11,13)(12,16)(14,18)(15,17)(19,21)(20,23)(22,24)(25,26)(27,35)(28,34)(29,32)(30,36)(31,33)(37,38)(39,40)(1,3,5,8)(2,6,4,7)(9,11,15,12)(10,16,17,13)(14,20,22,19)(18,21,24,23)(25,27,31,29)(26,32,33,35)(28,37,36,39)(30,38,34,40)(1,2,5,4)(3,6,8,7)(10,17)(11,12)(14,22)(21,23)(26,33)(28,36)(32,35)(37,39)(1,2,5,4)(3,6,8,7)(9,12,15,11)(10,16,17,13)(14,20,22,19)(18,23,24,21)(25,28,31,36)(26,34,33,30)(27,37,29,39)(32,40,35,38)(9,13,15,16)(10,12,17,11)(14,21,22,23)(18,20,24,19)(25,29,31,27)(26,35,33,32)(28,39,36,37)(30,40,34,38)(1,4,5,2)(3,7,8,6)(9,14,15,22)(10,18,17,24)(11,19,12,20)(13,21,16,23)(25,30,31,34)(26,36,33,28)(27,38,29,40)(32,39,35,37)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.