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