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