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