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