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