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