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