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