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